1 00:00:01,736 --> 00:00:05,604 Narrator: Alcatraz -- the most famous prison in the world, 2 00:00:05,606 --> 00:00:10,109 Where america's most notorious criminals are incarcerated. 3 00:00:10,111 --> 00:00:12,244 Harp: When you break the rules, you go to jail. 4 00:00:12,246 --> 00:00:15,180 When you break the rules in jail, you go to alcatraz. 5 00:00:15,182 --> 00:00:18,851 Narrator: Known as "the rock," designed to be inescapable... 6 00:00:18,853 --> 00:00:21,086 Komas: This place was built like a fortress. 7 00:00:21,088 --> 00:00:24,123 You have to wonder how anybody ever escaped from here. 8 00:00:24,125 --> 00:00:26,825 ...Only the most fearless would dare to try. 9 00:00:26,827 --> 00:00:30,829 All these layers of security, the thick concrete walls -- 10 00:00:30,831 --> 00:00:33,932 This was a place for the hard of the hardest criminals. 11 00:00:35,136 --> 00:00:37,169 Narrator: Now investigators use 12 00:00:37,171 --> 00:00:38,837 Innovative radar scanning equipment 13 00:00:38,839 --> 00:00:41,907 To uncover the island's secret past. 14 00:00:41,909 --> 00:00:43,809 Komas: These prisoners are telling us 15 00:00:43,811 --> 00:00:46,345 Something about their time here. 16 00:00:46,347 --> 00:00:48,113 Narrator: What really lies behind 17 00:00:48,115 --> 00:00:50,916 The prison's unbreakable reputation? 18 00:00:50,918 --> 00:00:53,919 Wow. It's completely destroyed. 19 00:00:53,921 --> 00:00:56,355 Narrator: To solve the mysteries of alcatraz, 20 00:00:56,357 --> 00:00:59,792 We'll break into this iconic jail, 21 00:00:59,794 --> 00:01:01,927 Blowing up its cell doors 22 00:01:01,929 --> 00:01:05,964 And stripping away its barbed wire-topped walls 23 00:01:05,966 --> 00:01:10,135 To reveal what finally breaks the rock. 24 00:01:10,137 --> 00:01:13,138 -- Captions by vitac -- www.Vitac.Com 25 00:01:13,140 --> 00:01:16,141 Captions paid for by discovery communications 26 00:01:16,143 --> 00:01:23,749 ♪ 27 00:01:23,751 --> 00:01:25,918 Alcatraz stands more than a mile 28 00:01:25,920 --> 00:01:29,455 Out into the waters of san francisco bay, 29 00:01:29,457 --> 00:01:34,693 Its iconic prison block a beacon of crime and punishment. 30 00:01:34,695 --> 00:01:36,595 For decades, this island is home 31 00:01:36,597 --> 00:01:40,766 To the most wanted men in america -- 32 00:01:40,768 --> 00:01:44,036 Al capone, machine gun kelly, 33 00:01:44,038 --> 00:01:47,306 Robert stroud, "the birdman." 34 00:01:47,308 --> 00:01:51,210 The convicts that came here couldn't be held anywhere else. 35 00:01:51,212 --> 00:01:53,011 Narrator: What engineering secrets 36 00:01:53,013 --> 00:01:55,848 Lie behind its legendary reputation? 37 00:01:57,952 --> 00:02:01,954 The rock is designed as a prison inside a prison. 38 00:02:01,956 --> 00:02:06,258 The outer wall is over 2 feet thick. 39 00:02:06,260 --> 00:02:13,665 Inside are over 300 cells stacked three stories high, 40 00:02:13,667 --> 00:02:17,870 And a 2-ton steel door blocks the only exit. 41 00:02:17,872 --> 00:02:21,073 ♪ 42 00:02:21,075 --> 00:02:25,544 Outside, 12-foot-tall fences topped with razor wire, 43 00:02:25,546 --> 00:02:28,947 All surrounded by six tall watchtowers 44 00:02:28,949 --> 00:02:31,783 With guards who shoot to kill. 45 00:02:31,785 --> 00:02:36,688 Alcatraz is the original supermax penitentiary, 46 00:02:36,690 --> 00:02:39,758 But why is the world's first maximum security prison 47 00:02:39,760 --> 00:02:41,093 Built here? 48 00:02:43,063 --> 00:02:48,433 In the 1800s, alcatraz island is home to a military fort. 49 00:02:48,435 --> 00:02:53,205 Historic buildings expert tanya komas wants to find out 50 00:02:53,207 --> 00:02:57,943 If this mysterious structure influences the later prison. 51 00:02:57,945 --> 00:03:00,112 She uses ground-penetrating radar 52 00:03:00,114 --> 00:03:03,582 To search for its hidden remains. 53 00:03:03,584 --> 00:03:05,617 We've been able to scan the wreck yard here, 54 00:03:05,619 --> 00:03:08,187 And this scan shows us something 55 00:03:08,189 --> 00:03:09,955 That we sort of knew might be there, 56 00:03:09,957 --> 00:03:12,558 And the science was able to confirm it. 57 00:03:12,560 --> 00:03:14,826 What we're looking at here is the recreation yard. 58 00:03:14,828 --> 00:03:16,328 The steps are here. 59 00:03:16,330 --> 00:03:18,797 There's the stairs and the cell houses up above. 60 00:03:18,799 --> 00:03:20,265 There is an actual structure 61 00:03:20,267 --> 00:03:23,468 Running east-west right beneath the wreck yard. 62 00:03:23,470 --> 00:03:26,738 Narrator: The scan locates a long earthen mound. 63 00:03:26,740 --> 00:03:29,474 Running beneath it is a masonry magazine, 64 00:03:29,476 --> 00:03:32,644 A structure used to store ammunition. 65 00:03:32,646 --> 00:03:35,547 This scan shows us that right under our feet here 66 00:03:35,549 --> 00:03:38,917 Is the historic military fortress. 67 00:03:38,919 --> 00:03:42,187 ♪ 68 00:03:42,189 --> 00:03:45,190 It's a part of a much bigger system of structures 69 00:03:45,192 --> 00:03:47,993 On this island. 70 00:03:47,995 --> 00:03:51,063 Narrator: In its prime, 200 soldiers operate 71 00:03:51,065 --> 00:03:54,733 The extensive arsenal of alcatraz's military fortress. 72 00:03:57,004 --> 00:03:59,805 Tanya thinks this earlier occupation of the island 73 00:03:59,807 --> 00:04:02,841 Shapes the development of the modern prison building. 74 00:04:02,843 --> 00:04:06,178 ♪ 75 00:04:06,180 --> 00:04:10,816 Buried under the main cellblocks lie the most substantial remains 76 00:04:10,818 --> 00:04:15,921 Of the military fort embedded into the bedrock. 77 00:04:15,923 --> 00:04:19,258 Bare rooms, some just 4 feet wide, 78 00:04:19,260 --> 00:04:22,594 With thin rifle slits for windows, 79 00:04:22,596 --> 00:04:24,630 Look out to a dry moat. 80 00:04:27,134 --> 00:04:31,470 This compound is made entirely from brick, 81 00:04:31,472 --> 00:04:35,674 But intriguingly, scratched out graffiti, names 82 00:04:35,676 --> 00:04:42,047 And dates reveal that these rooms once held people captive. 83 00:04:42,049 --> 00:04:45,317 Does alcatraz's reputation as a brutal lockup 84 00:04:45,319 --> 00:04:47,953 Go back much further than we think? 85 00:04:47,955 --> 00:04:51,723 ♪ 86 00:04:51,725 --> 00:04:55,727 Built in 1859, this underground basement 87 00:04:55,729 --> 00:04:58,397 Is part of the main defensive stronghold. 88 00:04:58,399 --> 00:05:00,632 ♪ 89 00:05:00,634 --> 00:05:04,369 Tanya has unique access to explore this dungeon. 90 00:05:06,974 --> 00:05:08,640 Komas: It would have been horrific 91 00:05:08,642 --> 00:05:10,208 To be in a cell like this. 92 00:05:10,210 --> 00:05:11,610 There are stories of people 93 00:05:11,612 --> 00:05:13,478 Sleeping on their hands and knees 94 00:05:13,480 --> 00:05:17,015 To avoid too much contact with the cold concrete. 95 00:05:17,017 --> 00:05:18,517 You wouldn't even know what time of day it is. 96 00:05:18,519 --> 00:05:20,752 This would not have been the place to be. 97 00:05:23,490 --> 00:05:25,457 Narrator: Laser scanning reveals 98 00:05:25,459 --> 00:05:28,393 The true extent of this hidden world. 99 00:05:28,395 --> 00:05:30,395 Built directly into the rock, 100 00:05:30,397 --> 00:05:34,666 The citadel is an incredible feat of engineering. 101 00:05:34,668 --> 00:05:37,269 This 3-d laser scan takes us down 102 00:05:37,271 --> 00:05:40,105 Into what's beneath the modern prison. 103 00:05:40,107 --> 00:05:41,440 This brick structure 104 00:05:41,442 --> 00:05:43,842 Was the largest structure on the island 105 00:05:43,844 --> 00:05:46,311 At that point in the island's history. 106 00:05:46,313 --> 00:05:48,647 This model is a great way to visualize 107 00:05:48,649 --> 00:05:51,583 Not only how the basement of the citadel was used, 108 00:05:51,585 --> 00:05:57,155 But these three spaces were among the first prison cells 109 00:05:57,157 --> 00:05:58,890 On alcatraz island. 110 00:06:00,994 --> 00:06:03,095 Narrator: During the military occupation, 111 00:06:03,097 --> 00:06:05,330 Engineers realized that the citadel is 112 00:06:05,332 --> 00:06:09,234 Much better suited as a military prison. 113 00:06:09,236 --> 00:06:12,137 By the end of the century, these small brick rooms 114 00:06:12,139 --> 00:06:15,273 Are filled with nearly 50 prisoners. 115 00:06:15,275 --> 00:06:18,844 The island's function as a prison is firmly established. 116 00:06:18,846 --> 00:06:22,748 ♪ 117 00:06:22,750 --> 00:06:27,018 How does alcatraz go from being a tiny military prison 118 00:06:27,020 --> 00:06:29,921 To the huge federal penitentiary we see today? 119 00:06:29,923 --> 00:06:33,658 ♪ 120 00:06:33,660 --> 00:06:36,161 The answer could lie with the darkest chapter 121 00:06:36,163 --> 00:06:39,364 In san francisco's history. 122 00:06:39,366 --> 00:06:42,801 In 1906, a massive earthquake, 123 00:06:42,803 --> 00:06:47,606 7.9 on the richter scale, destroys most of the city. 124 00:06:50,043 --> 00:06:52,411 But it leaves alcatraz standing. 125 00:06:52,413 --> 00:06:56,982 ♪ 126 00:06:56,984 --> 00:07:00,285 Tanya thinks this is a key to what makes alcatraz 127 00:07:00,287 --> 00:07:04,856 The prime location for a maximum security prison. 128 00:07:04,858 --> 00:07:08,360 To find out more about what happens during the quake, 129 00:07:08,362 --> 00:07:12,664 Tanya heads to meet geologist jack mayer. 130 00:07:12,666 --> 00:07:15,033 So why did alcatraz stand so strong 131 00:07:15,035 --> 00:07:17,903 When the rest of the city shook and fell? 132 00:07:17,905 --> 00:07:20,439 Well, this was the problem. 133 00:07:20,441 --> 00:07:23,742 This is the bay mud under san francisco. 134 00:07:23,744 --> 00:07:27,245 We know it's bay mud because of these shells. 135 00:07:27,247 --> 00:07:30,148 This stuff is extremely soft. 136 00:07:30,150 --> 00:07:32,050 When it's wet, it liquefies. 137 00:07:32,052 --> 00:07:33,952 Put under pressure, it shakes, 138 00:07:33,954 --> 00:07:37,422 And it shakes violently and unpredictably. 139 00:07:37,424 --> 00:07:39,558 That's the foundation of san francisco. 140 00:07:39,560 --> 00:07:40,759 That's amazing. 141 00:07:40,761 --> 00:07:42,861 No wonder the devastation of the earthquake. 142 00:07:42,863 --> 00:07:45,897 This is the stuff that fell apart when the earthquake came, 143 00:07:45,899 --> 00:07:48,733 And the buildings on top really didn't stand a chance. 144 00:07:50,571 --> 00:07:52,737 Narrator: Most of san francisco stands on land 145 00:07:52,739 --> 00:07:54,706 Reclaimed from the ocean. 146 00:07:54,708 --> 00:07:57,909 ♪ 147 00:07:57,911 --> 00:08:02,080 The bay mud allows the city to grow, 148 00:08:02,082 --> 00:08:04,983 But this soil is wet and soft. 149 00:08:04,985 --> 00:08:09,354 The 1906 quake turns the ground into quicksand. 150 00:08:09,356 --> 00:08:12,457 More than 28,000 buildings are destroyed, 151 00:08:12,459 --> 00:08:15,327 Including four of the city's prisons. 152 00:08:15,329 --> 00:08:19,731 Lines of evacuated convicts walked the streets, 153 00:08:19,733 --> 00:08:24,135 But the citadel in alcatraz sits directly on hard rock. 154 00:08:24,137 --> 00:08:26,004 The shock waves pass through it, 155 00:08:26,006 --> 00:08:29,307 And it survives the quake with barely a scratch. 156 00:08:31,044 --> 00:08:35,480 Alcatraz is the last functioning prison in san francisco, 157 00:08:35,482 --> 00:08:38,316 So the city ships its prisoners to the rock. 158 00:08:38,318 --> 00:08:44,623 ♪ 159 00:08:44,625 --> 00:08:48,093 This is the geology of alcatraz -- no sand, no mud. 160 00:08:48,095 --> 00:08:49,995 It's solid rock. 161 00:08:49,997 --> 00:08:51,596 It's easy to see how this would have performed 162 00:08:51,598 --> 00:08:52,931 In the earthquake. 163 00:08:52,933 --> 00:08:55,634 It would've stayed strong the entire time. 164 00:08:55,636 --> 00:08:59,704 ♪ 165 00:08:59,706 --> 00:09:02,274 Narrator: The island's bedrock lays the foundations 166 00:09:02,276 --> 00:09:05,510 For its unbreakable reputation. 167 00:09:05,512 --> 00:09:10,749 Soon after the quake, the iconic prison we see today is built. 168 00:09:10,751 --> 00:09:15,153 In 1934, the island becomes a federal penitentiary, 169 00:09:15,155 --> 00:09:19,124 Home to convicts no other prison can hold. 170 00:09:19,126 --> 00:09:20,692 But in the rush to build 171 00:09:20,694 --> 00:09:23,161 The world's first super prison here, 172 00:09:23,163 --> 00:09:26,064 Do engineers make fatal mistakes? 173 00:09:26,066 --> 00:09:29,901 ♪ 174 00:09:38,612 --> 00:09:41,346 ♪ 175 00:09:41,348 --> 00:09:45,149 Narrator: Alcatraz island in san francisco bay -- 176 00:09:45,151 --> 00:09:46,818 Convicts who have broken out 177 00:09:46,820 --> 00:09:50,689 Of every other prison in the u.S. Are brought here. 178 00:09:50,691 --> 00:09:52,023 To get ready for them, 179 00:09:52,025 --> 00:09:56,394 Engineers overhaul the building to maximum security. 180 00:09:56,396 --> 00:09:58,063 Harp: They completely revamped the place. 181 00:09:58,065 --> 00:10:00,899 It was fortified like a modern-day prison. 182 00:10:00,901 --> 00:10:03,168 Narrator: They install new hardened steel bars 183 00:10:03,170 --> 00:10:05,437 On every window and door, 184 00:10:05,439 --> 00:10:07,439 And a mechanical locking system 185 00:10:07,441 --> 00:10:10,408 With no keys for prisoners to steal. 186 00:10:10,410 --> 00:10:12,611 Harp: It's that whole mind-set of control. 187 00:10:12,613 --> 00:10:16,114 Once you're on alcatraz, they own you. 188 00:10:16,116 --> 00:10:17,449 Narrator: They arm the guards 189 00:10:17,451 --> 00:10:19,985 With the most up-to-date weapons. 190 00:10:19,987 --> 00:10:23,788 This new super prison is said to be escape-proof. 191 00:10:23,790 --> 00:10:25,991 [ door clanks, bird calls ] 192 00:10:25,993 --> 00:10:29,127 You get on this island, there's no getting off. 193 00:10:29,129 --> 00:10:33,465 Narrator: But in 1937, just three years after it opens, 194 00:10:33,467 --> 00:10:36,668 Two convicts, theodore cole and ralph roe, 195 00:10:36,670 --> 00:10:40,271 Find a chink in its armor. 196 00:10:40,273 --> 00:10:42,607 Rather than targeting the main cellblock, 197 00:10:42,609 --> 00:10:46,011 They turn their attention to the industries building. 198 00:10:46,013 --> 00:10:49,180 It's the block where the prisoners work, 199 00:10:49,182 --> 00:10:51,916 And it sits on the edge of the island. 200 00:10:54,421 --> 00:10:57,689 The men get to work in the blacksmith's workshop. 201 00:10:57,691 --> 00:11:00,458 After many weeks of sawing through the steel, 202 00:11:00,460 --> 00:11:03,995 Cole and roe tear out two bars 203 00:11:03,997 --> 00:11:07,565 And punch out unreinforced glass. 204 00:11:07,567 --> 00:11:10,435 Squeezing through the 9-inch gap, 205 00:11:10,437 --> 00:11:12,904 They drop down behind a 10-foot fence 206 00:11:12,906 --> 00:11:14,839 Topped with barbed wire 207 00:11:14,841 --> 00:11:16,808 And follow it to a small gate. 208 00:11:16,810 --> 00:11:18,009 [ metal clangs ] 209 00:11:18,011 --> 00:11:20,979 They smash the lock with a stolen wrench, 210 00:11:20,981 --> 00:11:24,549 And, the theory goes, they use old car tires 211 00:11:24,551 --> 00:11:28,486 To cushion the 20-foot jump down onto the hard rock 212 00:11:28,488 --> 00:11:33,158 And old fuel canisters to float off the island. 213 00:11:33,160 --> 00:11:36,094 How could they escape the most secure jail on earth 214 00:11:36,096 --> 00:11:37,862 In broad daylight? 215 00:11:37,864 --> 00:11:41,866 ♪ 216 00:11:41,868 --> 00:11:45,270 Retired fbi agent jeff harp has spent a career 217 00:11:45,272 --> 00:11:48,339 Putting bad guys behind bars. 218 00:11:48,341 --> 00:11:51,976 He investigates alcatraz's escape attempts. 219 00:11:51,978 --> 00:11:54,446 Harp: You had to be a very determined prisoner 220 00:11:54,448 --> 00:11:57,716 To get out of this place. 221 00:11:57,718 --> 00:11:59,084 Narrator: He wants to find out 222 00:11:59,086 --> 00:12:00,752 If the prison's famous reputation 223 00:12:00,754 --> 00:12:04,989 Hides a fatal flaw in its construction. 224 00:12:04,991 --> 00:12:07,726 Jeff believes that the workshop is a weak spot 225 00:12:07,728 --> 00:12:11,896 That helps cole and roe to escape. 226 00:12:11,898 --> 00:12:14,699 Harp: They had access to all sorts of tools and equipment 227 00:12:14,701 --> 00:12:16,701 To build things while they were thinking about 228 00:12:16,703 --> 00:12:19,871 How they might be able to escape. 229 00:12:19,873 --> 00:12:21,406 Narrator: A 3-d model reveals 230 00:12:21,408 --> 00:12:25,744 How the men turned the block's floor plan to their advantage. 231 00:12:25,746 --> 00:12:28,413 So as you can see from the design of the this building, 232 00:12:28,415 --> 00:12:30,749 Prisoners had a lot of places to hide. 233 00:12:30,751 --> 00:12:34,552 As the guard's making his pathway up this wall here, 234 00:12:34,554 --> 00:12:35,920 He can't see into these rooms 235 00:12:35,922 --> 00:12:38,523 Until he's directly in front of the doorways. 236 00:12:40,160 --> 00:12:43,495 Narrator: The industries building is l-shaped, 237 00:12:43,497 --> 00:12:47,899 The ground floor divided into eight sections. 238 00:12:47,901 --> 00:12:49,300 It's poorly designed. 239 00:12:49,302 --> 00:12:52,771 It's not functional from a law enforcement perspective. 240 00:12:52,773 --> 00:12:56,841 Narrator: The workshop itself provides the tools the men need. 241 00:12:56,843 --> 00:13:01,746 They slowly saw through window bars using stolen hacksaws. 242 00:13:01,748 --> 00:13:04,282 So each time the guard had his back turned, 243 00:13:04,284 --> 00:13:06,618 The inmate would be able to go back to the window 244 00:13:06,620 --> 00:13:09,721 And cut on the steel bar little by little. 245 00:13:09,723 --> 00:13:12,524 Narrator: The prisoners jump out of the window. 246 00:13:12,526 --> 00:13:15,026 What they do next seems incredible. 247 00:13:16,429 --> 00:13:18,730 The breakout point is just 30 feet away 248 00:13:18,732 --> 00:13:21,065 From the guards on the roof, 249 00:13:21,067 --> 00:13:23,668 So the escapees creep along the side of the building 250 00:13:23,670 --> 00:13:25,837 To hide from view. 251 00:13:25,839 --> 00:13:27,505 But once they reach the coast, 252 00:13:27,507 --> 00:13:29,240 The guards on the western watchtower 253 00:13:29,242 --> 00:13:31,409 Should easily spot them, 254 00:13:31,411 --> 00:13:33,845 So how do they manage to stay out of view? 255 00:13:33,847 --> 00:13:38,883 ♪ 256 00:13:38,885 --> 00:13:41,419 Jeff thinks that the bay's unusual weather 257 00:13:41,421 --> 00:13:44,989 Helps to conceal the men's escape. 258 00:13:44,991 --> 00:13:46,858 From the case files, we found out 259 00:13:46,860 --> 00:13:49,227 That the fog on that day was unusually thick, 260 00:13:49,229 --> 00:13:52,497 So it's quite possible that cole and roe deliberately waited 261 00:13:52,499 --> 00:13:57,735 That day for the heavy fog to come into san francisco. 262 00:13:57,737 --> 00:14:00,038 Narrator: San francisco is one of the foggiest cities 263 00:14:00,040 --> 00:14:01,806 On the planet. 264 00:14:03,310 --> 00:14:05,977 Sea mist can become so dense that it hides 265 00:14:05,979 --> 00:14:09,647 Even the gigantic golden gate bridge. 266 00:14:09,649 --> 00:14:11,449 ♪ 267 00:14:11,451 --> 00:14:14,619 Jeff visits an outdoor weather simulator to find out 268 00:14:14,621 --> 00:14:19,123 If fog is the key to cole and roe's success. 269 00:14:19,125 --> 00:14:22,393 Between these two piers, we have a fog simulator 270 00:14:22,395 --> 00:14:23,828 That spews out seawater 271 00:14:23,830 --> 00:14:27,632 To simulate the fog in san francisco. 272 00:14:27,634 --> 00:14:31,369 Narrator: Jeff is going to carry out a test to try to replicate 273 00:14:31,371 --> 00:14:35,607 What he thinks happens during the escape. 274 00:14:35,609 --> 00:14:38,376 Harp: Once the fog starts, we'll be able to determine 275 00:14:38,378 --> 00:14:42,247 How effective it was at concealing their movement. 276 00:14:42,249 --> 00:14:44,315 Narrator: The fog machine fires up. 277 00:14:44,317 --> 00:14:51,956 ♪ 278 00:14:51,958 --> 00:14:56,060 Jeff's test subject walks down the bridge. 279 00:14:56,062 --> 00:15:00,131 After a dozen paces, she vanishes. 280 00:15:02,636 --> 00:15:06,004 Harp: She has completely disappeared on the bridge. 281 00:15:06,006 --> 00:15:09,140 We're going to measure that out and see what that distance is. 282 00:15:14,881 --> 00:15:17,849 15.4 meters. 283 00:15:17,851 --> 00:15:20,785 This would be a really effective concealment and cover 284 00:15:20,787 --> 00:15:22,787 For the individuals who were trying 285 00:15:22,789 --> 00:15:26,324 To escape from the prison that day. 286 00:15:26,326 --> 00:15:28,860 Narrator: The test reveals how fog could render 287 00:15:28,862 --> 00:15:31,863 The prison's watchtowers useless, 288 00:15:31,865 --> 00:15:34,198 But the same weather that helps cole and roe 289 00:15:34,200 --> 00:15:37,302 Escape the rock soon turns against them. 290 00:15:37,304 --> 00:15:40,738 ♪ 291 00:15:40,740 --> 00:15:43,107 The fog was effective at concealing their movement, 292 00:15:43,109 --> 00:15:45,343 But once they got out to sea, it was their enemy 293 00:15:45,345 --> 00:15:48,746 Because they could not see where they were going. 294 00:15:48,748 --> 00:15:51,149 Narrator: Back in 1937, 295 00:15:51,151 --> 00:15:55,653 Fbi investigators conclude that the men drowned. 296 00:15:55,655 --> 00:15:58,256 The case is closed. 297 00:15:58,258 --> 00:16:02,293 Alcatraz quietly gets a new industries block 298 00:16:02,295 --> 00:16:06,931 With no dead corners and new harder steel bars. 299 00:16:06,933 --> 00:16:12,236 This time, authorities think there really is no way out. 300 00:16:12,238 --> 00:16:15,373 But do they make another simple design mistake 301 00:16:15,375 --> 00:16:19,010 In trying to outwit america's toughest cons? 302 00:16:19,012 --> 00:16:22,347 ♪ 303 00:16:31,191 --> 00:16:32,824 ♪ 304 00:16:32,826 --> 00:16:34,659 Narrator: Alcatraz -- 305 00:16:34,661 --> 00:16:38,496 The toughest place to do time. 306 00:16:38,498 --> 00:16:40,665 After an overhaul, the prison is ready 307 00:16:40,667 --> 00:16:44,302 To hold the worst criminals in america. 308 00:16:46,239 --> 00:16:47,438 These guys are outlaws. 309 00:16:47,440 --> 00:16:49,340 As soon as they step foot on this island, 310 00:16:49,342 --> 00:16:51,309 They've got to be thinking about escape. 311 00:16:53,780 --> 00:16:57,181 Narrator: Historic buildings expert tanya komas investigates 312 00:16:57,183 --> 00:17:01,786 How engineers try to seal every weak point in alcatraz. 313 00:17:01,788 --> 00:17:05,857 But building on a rocky island is a real challenge. 314 00:17:05,859 --> 00:17:09,761 Tanya discovers how the workers cut corners. 315 00:17:09,763 --> 00:17:11,529 Komas: Construction on an island 316 00:17:11,531 --> 00:17:13,531 Meant that materials are hard to get. 317 00:17:13,533 --> 00:17:16,667 When the cell bars were replaced in the prison, 318 00:17:16,669 --> 00:17:18,569 Rather than discard them, they were used 319 00:17:18,571 --> 00:17:21,239 As reinforcing into the concrete. 320 00:17:21,241 --> 00:17:23,007 Good old prison labor, right here. 321 00:17:23,009 --> 00:17:26,644 ♪ 322 00:17:26,646 --> 00:17:31,549 Narrator: Despite this, alcatraz is still a formidable fortress. 323 00:17:31,551 --> 00:17:35,920 The guards step up security to unprecedented levels. 324 00:17:35,922 --> 00:17:38,056 There was three guards for every one prisoner, 325 00:17:38,058 --> 00:17:40,258 Which is unheard of for that time. 326 00:17:40,260 --> 00:17:42,593 Narrator: In 1937, the island gets 327 00:17:42,595 --> 00:17:45,663 A more secure industries building. 328 00:17:45,665 --> 00:17:47,899 Now authorities think they finally have 329 00:17:47,901 --> 00:17:50,668 The ultimate escape-proof prison. 330 00:17:50,670 --> 00:17:52,503 Well, when the inmates walked on this island, 331 00:17:52,505 --> 00:17:53,738 They saw this place. 332 00:17:53,740 --> 00:17:55,239 They knew that it was going to be a challenge 333 00:17:55,241 --> 00:17:56,574 To ever break out of here. 334 00:17:56,576 --> 00:18:00,244 ♪ 335 00:18:00,246 --> 00:18:01,846 Narrator: What few know is that 336 00:18:01,848 --> 00:18:05,716 The new alcatraz still has a fatal flaw. 337 00:18:05,718 --> 00:18:09,353 And on Friday the 13th, 1939, 338 00:18:09,355 --> 00:18:11,989 Five men exploit this weakness, 339 00:18:11,991 --> 00:18:14,926 Led by one of america's most dangerous men, 340 00:18:14,928 --> 00:18:16,894 Arthur "doc" barker. 341 00:18:18,598 --> 00:18:20,364 When the guards aren't looking, 342 00:18:20,366 --> 00:18:23,601 The five men target their cell bars. 343 00:18:23,603 --> 00:18:24,936 [ doors clank ] 344 00:18:24,938 --> 00:18:27,505 They use blades to cut through the steel 345 00:18:27,507 --> 00:18:30,842 And swing the bars open. 346 00:18:30,844 --> 00:18:36,114 All five inmates are now able to escape to their cells. 347 00:18:36,116 --> 00:18:39,750 In the corridor, they face a concrete wall 348 00:18:39,752 --> 00:18:42,820 With thick steel grilles covering the windows, 349 00:18:44,991 --> 00:18:48,626 But they break a 1-inch-thick bar clean off 350 00:18:48,628 --> 00:18:51,329 And smash through the iron window frame. 351 00:18:51,331 --> 00:18:53,464 [ metal clanks ] 352 00:18:54,901 --> 00:18:57,168 They've broken the block. 353 00:18:57,170 --> 00:18:58,936 How do they manage to beat 354 00:18:58,938 --> 00:19:01,506 The unbreakable steel of alcatraz? 355 00:19:04,043 --> 00:19:07,245 Jeff harp examines the evidence. 356 00:19:07,247 --> 00:19:10,414 Harp: These five guys were in the isolation block, d-block. 357 00:19:10,416 --> 00:19:12,116 It was supposed to be the most secure block 358 00:19:12,118 --> 00:19:14,852 In the whole penitentiary. 359 00:19:14,854 --> 00:19:16,787 Narrator: The notorious d-block 360 00:19:16,789 --> 00:19:19,290 Houses convicts who break the rules. 361 00:19:19,292 --> 00:19:24,061 Here, they spend 24 hours a day in isolation. 362 00:19:24,063 --> 00:19:26,731 But the evidence shows that the cells aren't as tough 363 00:19:26,733 --> 00:19:29,901 As they should be. 364 00:19:29,903 --> 00:19:31,736 Harp: When I read the fbi document, 365 00:19:31,738 --> 00:19:35,039 I see that d-block, where the worst prisoners are kept, 366 00:19:35,041 --> 00:19:37,408 Is made of ordinary steel bars. 367 00:19:39,145 --> 00:19:42,713 Narrator: When engineers upgrade the prison to maximum security, 368 00:19:42,715 --> 00:19:48,085 They fit most cells with strengthened tool-proof bars. 369 00:19:48,087 --> 00:19:52,623 But incredibly, those in d-block retain the original steel, 370 00:19:52,625 --> 00:19:56,460 A hangover of the prison's military past. 371 00:19:56,462 --> 00:19:57,929 Over time, little by little, 372 00:19:57,931 --> 00:19:59,931 These guys would've been able to saw through these bars 373 00:19:59,933 --> 00:20:02,767 Because it was so soft. 374 00:20:02,769 --> 00:20:05,169 Narrator: The men use smuggled hacksaw blades, 375 00:20:05,171 --> 00:20:08,673 Working undetected night after night. 376 00:20:08,675 --> 00:20:12,210 But this is only stage one of their escape. 377 00:20:12,212 --> 00:20:13,844 So after they broke out of their cells, 378 00:20:13,846 --> 00:20:15,780 They had a new challenge they had to face, 379 00:20:15,782 --> 00:20:19,650 And they came up against the windows with hardened steel. 380 00:20:19,652 --> 00:20:21,152 Narrator: Unlike their cell bars, 381 00:20:21,154 --> 00:20:24,555 The windows in the main block do get the upgrade. 382 00:20:24,557 --> 00:20:28,993 Thick, tool-proof bars now block their route to the outside, 383 00:20:28,995 --> 00:20:31,929 Yet still, the men find a way out. 384 00:20:31,931 --> 00:20:34,265 Harp: It looks like they had some sort of a tool, 385 00:20:34,267 --> 00:20:36,100 Where they had pried open the window 386 00:20:36,102 --> 00:20:39,403 And were able to snap those bars. 387 00:20:39,405 --> 00:20:42,006 Narrator: Fbi documents reveal that the men create 388 00:20:42,008 --> 00:20:43,908 A homemade screw jack, 389 00:20:43,910 --> 00:20:48,646 Essentially a large screw with a bolt on the end. 390 00:20:48,648 --> 00:20:50,948 They turn the screw until finally, 391 00:20:50,950 --> 00:20:53,150 The bar snaps right off. 392 00:20:53,152 --> 00:20:56,320 ♪ 393 00:20:56,322 --> 00:20:57,888 Just after 3:00 a.M., 394 00:20:57,890 --> 00:21:00,758 The men attempt the last part of their plan. 395 00:21:03,329 --> 00:21:07,398 They squeeze through the window and sprint for the cliffs, 396 00:21:07,400 --> 00:21:10,001 Avoiding the gaze of the guards. 397 00:21:10,003 --> 00:21:12,837 Then they split up. 398 00:21:12,839 --> 00:21:15,773 Mccain and young start work on a raft, 399 00:21:15,775 --> 00:21:19,677 Making it from 3-inch timber, driftwood, and a chair. 400 00:21:19,679 --> 00:21:23,714 They tie it all together with torn bedsheets. 401 00:21:23,716 --> 00:21:26,050 Barker and stamphill head around the coast 402 00:21:26,052 --> 00:21:27,885 To collect more driftwood, 403 00:21:27,887 --> 00:21:30,154 While martin scales the cliffs at the point 404 00:21:30,156 --> 00:21:33,958 Facing san francisco and starts swimming alone, 405 00:21:33,960 --> 00:21:36,727 But at 4:00 a.M., the guards notice they're missing 406 00:21:36,729 --> 00:21:38,529 And launch a manhunt. 407 00:21:38,531 --> 00:21:41,999 Three men surrender, but two try to swim... 408 00:21:42,001 --> 00:21:44,702 [ rapid gunfire ] ...And the guards open fire. 409 00:21:46,739 --> 00:21:50,508 Only four men eventually return to the cells. 410 00:21:50,510 --> 00:21:54,211 Doc barker dies in a hospital from gunshot wounds. 411 00:21:55,648 --> 00:21:57,148 After the failed escape, 412 00:21:57,150 --> 00:22:01,619 D-block finally gets its security upgrade. 413 00:22:01,621 --> 00:22:05,222 Engineers put hardened steel bars on every cell, 414 00:22:05,224 --> 00:22:09,493 Convinced it's now impossible to escape the prison cellblock. 415 00:22:10,863 --> 00:22:15,166 Over the next 23 years, 20 more convicts try and fail 416 00:22:15,168 --> 00:22:17,301 To break out of the prison. 417 00:22:17,303 --> 00:22:21,138 Each winds up dead or back in their cells. 418 00:22:21,140 --> 00:22:24,775 But in 1962, three men hatch a plan to pull off 419 00:22:24,777 --> 00:22:28,813 The most audacious prison break in history. 420 00:22:28,815 --> 00:22:31,315 Komas: This is right where they were able to dig out 421 00:22:31,317 --> 00:22:34,185 And then climb right up there. 422 00:22:34,187 --> 00:22:36,854 Narrator: Some people claim it takes them to freedom. 423 00:22:36,856 --> 00:22:39,390 ♪ 424 00:22:39,392 --> 00:22:43,060 Are they the only men to escape from alcatraz? 425 00:22:43,062 --> 00:22:47,565 ♪ 426 00:22:56,376 --> 00:22:57,575 ♪ 427 00:22:57,577 --> 00:22:59,043 Narrator: In the 1960s, 428 00:22:59,045 --> 00:23:03,748 Alcatraz is the most secure prison in the world, 429 00:23:03,750 --> 00:23:08,185 Home to convicts that no other penitentiary can hold. 430 00:23:08,187 --> 00:23:10,755 Dozens try to escape. 431 00:23:10,757 --> 00:23:14,158 All fail to break the rock. 432 00:23:14,160 --> 00:23:17,762 But on the morning of June 12, 1962, 433 00:23:17,764 --> 00:23:19,263 One daring prison break 434 00:23:19,265 --> 00:23:21,632 Threatens to ruin its perfect record. 435 00:23:21,634 --> 00:23:24,668 ♪ 436 00:23:24,670 --> 00:23:29,173 During a routine head count, guards sound the alarm. 437 00:23:29,175 --> 00:23:32,510 Frank morris and john and clarence anglin 438 00:23:32,512 --> 00:23:35,479 Are missing. 439 00:23:35,481 --> 00:23:38,616 The escape begins at lights out. 440 00:23:38,618 --> 00:23:40,017 To fool the guards, 441 00:23:40,019 --> 00:23:42,987 The prisoners use dummy heads with real hair 442 00:23:42,989 --> 00:23:46,056 Stolen from the prison barbershop. 443 00:23:46,058 --> 00:23:49,026 Under the sink, a fake cardboard vent 444 00:23:49,028 --> 00:23:51,595 Reveals a gaping hole in the concrete 445 00:23:51,597 --> 00:23:54,565 Carved out of over months. 446 00:23:54,567 --> 00:23:57,001 Crawling into the utility corridor, 447 00:23:57,003 --> 00:24:00,538 They climb 30 feet up the pipes 448 00:24:00,540 --> 00:24:03,073 And bend the bars on a ceiling grille 449 00:24:03,075 --> 00:24:06,811 To break onto the roof. 450 00:24:06,813 --> 00:24:11,582 Sliding 50 feet down a pipe and scaling a barbed wire fence, 451 00:24:11,584 --> 00:24:14,385 Morris and the anglin brothers reach the ocean, 452 00:24:14,387 --> 00:24:16,153 Never to be seen again. 453 00:24:19,158 --> 00:24:21,559 Historic buildings expert tanya komas 454 00:24:21,561 --> 00:24:24,428 Specializes in working with concrete. 455 00:24:24,430 --> 00:24:26,263 She thinks a key to this breakout 456 00:24:26,265 --> 00:24:31,602 Lies with a structural flaw in the walls themselves. 457 00:24:31,604 --> 00:24:34,071 She has come to the engineering laboratory 458 00:24:34,073 --> 00:24:37,174 At the university of california in berkeley, 459 00:24:37,176 --> 00:24:40,478 Which specializes in testing different types of concrete. 460 00:24:42,415 --> 00:24:43,914 Komas: Concrete is a simple mix 461 00:24:43,916 --> 00:24:45,683 Of sand, cement, rocks, and water. 462 00:24:45,685 --> 00:24:47,017 It's very important that they be 463 00:24:47,019 --> 00:24:48,385 In the right proportions, though. 464 00:24:48,387 --> 00:24:49,753 You put in a little too much water 465 00:24:49,755 --> 00:24:51,021 To make it easier to work with, 466 00:24:51,023 --> 00:24:53,624 And you've greatly reduced its strength. 467 00:24:53,626 --> 00:24:57,828 Narrator: First, she needs to look at the evidence. 468 00:24:57,830 --> 00:25:00,097 Komas: We're looking at one of the vents that the prisoners 469 00:25:00,099 --> 00:25:02,600 Chiseled their way out of. 470 00:25:02,602 --> 00:25:03,934 Now if you're one of the visitors 471 00:25:03,936 --> 00:25:06,604 Who walk by this cell in alcatraz, 472 00:25:06,606 --> 00:25:08,539 This might look like normal concrete. 473 00:25:08,541 --> 00:25:11,775 But looking closer, you can see large stones, 474 00:25:11,777 --> 00:25:15,145 A lot of them, very close together. 475 00:25:15,147 --> 00:25:18,682 Narrator: Alcatraz-style concrete looks rough and ready. 476 00:25:18,684 --> 00:25:20,518 Tanya uses a compression machine 477 00:25:20,520 --> 00:25:23,220 To compare it with a modern sample. 478 00:25:23,222 --> 00:25:24,522 Komas: I have two concrete samples here. 479 00:25:24,524 --> 00:25:27,758 One is a good proportion of materials properly mixed, 480 00:25:27,760 --> 00:25:30,027 And the other, we know to be a poor mix -- 481 00:25:30,029 --> 00:25:34,765 Not well-blended materials and not the right proportions. 482 00:25:34,767 --> 00:25:36,567 Narrator: The compression machine will steadily 483 00:25:36,569 --> 00:25:39,136 Apply pressure to the concrete sample 484 00:25:39,138 --> 00:25:41,739 Up to the point where the concrete fails. 485 00:25:41,741 --> 00:25:44,742 ♪ 486 00:25:44,744 --> 00:25:46,877 First, the modern concrete. 487 00:25:48,548 --> 00:25:50,414 Let's start the test. 488 00:25:50,416 --> 00:25:53,284 Narrator: The pressure applied is measured in pounds. 489 00:25:53,286 --> 00:25:54,919 [ whirring ] 490 00:25:54,921 --> 00:25:58,923 You can see, it's already climbing pretty quickly. 491 00:25:58,925 --> 00:26:02,059 We're now at 75,000 pounds of pressure on this sample, 492 00:26:02,061 --> 00:26:04,061 And it's still holding strong. 493 00:26:05,765 --> 00:26:08,899 Okay, we're at 120,000 pounds of pressure now. 494 00:26:08,901 --> 00:26:10,901 [ cracking ] 495 00:26:10,903 --> 00:26:14,104 We're starting to see a little bit of crumbling. 496 00:26:14,106 --> 00:26:15,706 It's starting to fail. 497 00:26:15,708 --> 00:26:19,009 ♪ 498 00:26:19,011 --> 00:26:24,748 Narrator: The sample withstands an incredible 128,000 pounds. 499 00:26:24,750 --> 00:26:27,117 Komas: That's really high-strength concrete. 500 00:26:27,119 --> 00:26:32,856 That is approximately 40, 42 automobiles of pressure. 501 00:26:32,858 --> 00:26:36,126 Narrator: And now the type of concrete used at alcatraz. 502 00:26:36,128 --> 00:26:39,663 ♪ 503 00:26:39,665 --> 00:26:42,733 [ whirring ] 504 00:26:42,735 --> 00:26:45,703 Komas: 40,000 pounds. 505 00:26:45,705 --> 00:26:47,638 65,000. 506 00:26:47,640 --> 00:26:48,806 [ cracking ] 507 00:26:48,808 --> 00:26:51,008 It's already shown some failure. 508 00:26:51,010 --> 00:26:54,478 ♪ 509 00:26:54,480 --> 00:26:56,080 70,000. 510 00:26:56,082 --> 00:27:03,053 ♪ 511 00:27:03,055 --> 00:27:05,856 Whoa. There we go. 512 00:27:05,858 --> 00:27:09,026 Wow. Look at this. 513 00:27:09,028 --> 00:27:11,395 Only about half of the force of the other sample, 514 00:27:11,397 --> 00:27:14,531 And it's completely destroyed. 515 00:27:14,533 --> 00:27:16,600 Narrator: This sample fails and crumbles 516 00:27:16,602 --> 00:27:19,903 At just 70,000 pounds. 517 00:27:19,905 --> 00:27:21,772 So if you're a prisoner on alcatraz, 518 00:27:21,774 --> 00:27:22,973 This would be the kind of concrete 519 00:27:22,975 --> 00:27:24,475 You would want in your cell. 520 00:27:24,477 --> 00:27:27,177 ♪ 521 00:27:27,179 --> 00:27:29,179 The guys were able to use homemade tools -- 522 00:27:29,181 --> 00:27:32,483 Spoons, chisels, and a very small, kind of crude motor 523 00:27:32,485 --> 00:27:34,485 From a vacuum cleaner. 524 00:27:34,487 --> 00:27:38,389 That was enough to chisel your way to freedom. 525 00:27:38,391 --> 00:27:41,125 Narrator: It is prisoners, not engineers, 526 00:27:41,127 --> 00:27:44,328 Who build the cellblock in 1909. 527 00:27:44,330 --> 00:27:46,063 Over half a century later, 528 00:27:46,065 --> 00:27:49,733 Prisoners during the escape were potentially assisted 529 00:27:49,735 --> 00:27:53,537 By their predecessors who created this structure. 530 00:27:53,539 --> 00:27:55,305 Narrator: Poor construction means 531 00:27:55,307 --> 00:27:58,108 The concrete is weak from the start, 532 00:27:58,110 --> 00:27:59,576 But tanya is convinced 533 00:27:59,578 --> 00:28:01,945 That it should still be able to withstand 534 00:28:01,947 --> 00:28:05,015 The convicts chipping it away with just homemade tools. 535 00:28:05,017 --> 00:28:07,284 ♪ 536 00:28:07,286 --> 00:28:10,020 She has special access inside alcatraz 537 00:28:10,022 --> 00:28:11,889 To examine the original hole 538 00:28:11,891 --> 00:28:14,992 That one of the anglin brothers escapes through. 539 00:28:14,994 --> 00:28:16,627 Komas: This is cellblock b. 540 00:28:16,629 --> 00:28:21,699 ♪ 541 00:28:21,701 --> 00:28:23,067 So what we're looking at is the hole 542 00:28:23,069 --> 00:28:25,436 That one of the escapees broke out of. 543 00:28:25,438 --> 00:28:27,438 You can see that the concrete has just been 544 00:28:27,440 --> 00:28:29,606 Completely destroyed. 545 00:28:29,608 --> 00:28:30,974 This is one of the sounds we love to hear 546 00:28:30,976 --> 00:28:33,310 In the concrete world when you're doing repair is... 547 00:28:33,312 --> 00:28:35,279 [ hollow tapping ] that hollow, 548 00:28:35,281 --> 00:28:38,482 The sound of cracking inside of that concrete. 549 00:28:38,484 --> 00:28:39,983 That would've made it much easier for them 550 00:28:39,985 --> 00:28:42,453 To chip away at it and get the grate out 551 00:28:42,455 --> 00:28:45,155 And then climb right up there. 552 00:28:46,726 --> 00:28:48,859 Narrator: Tanya thinks the problem with the concrete 553 00:28:48,861 --> 00:28:52,396 Lies with the sea air that surrounds the prison. 554 00:28:52,398 --> 00:28:54,865 Steel reinforcements embedded in the walls 555 00:28:54,867 --> 00:28:58,335 Are slowly being exposed to the elements. 556 00:28:58,337 --> 00:28:59,636 Tanya and her team 557 00:28:59,638 --> 00:29:01,672 From the concrete preservation institute 558 00:29:01,674 --> 00:29:05,809 Are in a race to preserve the island's structures. 559 00:29:05,811 --> 00:29:08,779 Komas: If you look here, this bar has corroded, 560 00:29:08,781 --> 00:29:10,714 Popped the concrete right off. 561 00:29:10,716 --> 00:29:12,616 We're in this very aggressive seaside environment. 562 00:29:12,618 --> 00:29:17,554 The salt gets in, and you just have steel corrosion. 563 00:29:17,556 --> 00:29:20,290 Narrator: Saltwater gets into the smallest of cracks 564 00:29:20,292 --> 00:29:24,928 And corrodes steel five times faster than fresh water. 565 00:29:24,930 --> 00:29:26,463 Komas: The steel rusts, 566 00:29:26,465 --> 00:29:29,266 And it can expand up to six times its size. 567 00:29:29,268 --> 00:29:31,502 What that does is put internal pressure on the concrete, 568 00:29:31,504 --> 00:29:35,672 Causes cracks, and pushes the concrete right off. 569 00:29:35,674 --> 00:29:39,243 Narrator: Salt attacks alcatraz from all angles. 570 00:29:41,447 --> 00:29:45,949 Alcatraz uses seawater to flush the toilets. 571 00:29:45,951 --> 00:29:50,921 It trickles from leaky pipes and seeps into the walls. 572 00:29:50,923 --> 00:29:54,858 The salt rusts the reinforcing steel bars. 573 00:29:54,860 --> 00:29:59,363 They expand, cracking the concrete. 574 00:29:59,365 --> 00:30:01,465 Officials believe an island location 575 00:30:01,467 --> 00:30:04,935 Is one of the prison's greatest advantages. 576 00:30:04,937 --> 00:30:07,538 No one anticipates it is, in fact, 577 00:30:07,540 --> 00:30:10,774 One of its biggest weaknesses. 578 00:30:10,776 --> 00:30:12,643 Komas: The design and construction of this building, 579 00:30:12,645 --> 00:30:15,245 The unbreakable alcatraz, 580 00:30:15,247 --> 00:30:17,881 Is what ended up being a key factor 581 00:30:17,883 --> 00:30:22,653 In one of the most notorious prison escapes ever known. 582 00:30:22,655 --> 00:30:24,121 Narrator: Morris and the anglin brothers 583 00:30:24,123 --> 00:30:27,858 Don't just spend their time chiseling away at the concrete. 584 00:30:27,860 --> 00:30:29,860 They also find an ingenious way 585 00:30:29,862 --> 00:30:33,964 To execute the rest of their escape. 586 00:30:33,966 --> 00:30:36,567 During their daytime cleaning duties, 587 00:30:36,569 --> 00:30:38,602 They hang sheets on the top floor 588 00:30:38,604 --> 00:30:41,171 To stop dust falling into the prison, 589 00:30:41,173 --> 00:30:43,507 Cleverly obscuring the guards' view. 590 00:30:46,345 --> 00:30:48,145 Every night for six weeks, 591 00:30:48,147 --> 00:30:51,415 The inmates take turns to escape their cells 592 00:30:51,417 --> 00:30:55,652 And climb to the workshop to work on the escape equipment. 593 00:30:55,654 --> 00:30:58,522 Inspired by an engineering magazine, 594 00:30:58,524 --> 00:31:02,426 They design a raft made from 50 raincoats. 595 00:31:02,428 --> 00:31:06,997 They use steam from pipes to bond them together. 596 00:31:06,999 --> 00:31:08,498 They make life jackets 597 00:31:08,500 --> 00:31:11,535 And transform an accordion into a pump, 598 00:31:11,537 --> 00:31:14,271 Ready for a quick getaway on the big night. 599 00:31:14,273 --> 00:31:20,477 ♪ 600 00:31:20,479 --> 00:31:24,581 Once again, the cellblock's design aids an escape, 601 00:31:24,583 --> 00:31:26,016 But morris and the anglin brothers 602 00:31:26,018 --> 00:31:28,819 Still have to get off the island. 603 00:31:28,821 --> 00:31:30,621 As they race to the shoreline, 604 00:31:30,623 --> 00:31:33,957 Their hopes are now pinned on their homemade raft. 605 00:31:36,295 --> 00:31:42,065 The waters around alcatraz are its last line of defense. 606 00:31:42,067 --> 00:31:44,568 Prison authorities believe no one can conquer 607 00:31:44,570 --> 00:31:47,638 San francisco bay. 608 00:31:47,640 --> 00:31:50,807 But is relying on the island's isolated location 609 00:31:50,809 --> 00:31:52,609 Their greatest mistake? 610 00:31:52,611 --> 00:31:58,315 ♪ 611 00:32:07,192 --> 00:32:08,425 ♪ 612 00:32:08,427 --> 00:32:10,294 Narrator: In 1962, 613 00:32:10,296 --> 00:32:12,562 The federal penitentiary on alcatraz 614 00:32:12,564 --> 00:32:16,266 Holds more than 250 convicts. 615 00:32:16,268 --> 00:32:19,770 No one has ever successfully escaped. 616 00:32:19,772 --> 00:32:21,238 But on June 11th, 617 00:32:21,240 --> 00:32:26,276 The rock's unbreakable reputation hangs in the balance. 618 00:32:26,278 --> 00:32:28,178 Three escaped convicts -- 619 00:32:28,180 --> 00:32:31,648 Frank morris and brothers john and clarence anglin -- 620 00:32:31,650 --> 00:32:35,519 Stand at the water's edge. 621 00:32:35,521 --> 00:32:39,923 They have an improvised raft made from raincoats. 622 00:32:39,925 --> 00:32:42,826 Freedom is within reach, 623 00:32:42,828 --> 00:32:45,228 But these are treacherous waters. 624 00:32:47,766 --> 00:32:52,836 Draining away the bay reveals hidden dangers. 625 00:32:52,838 --> 00:32:54,805 Across the rocky seafloor 626 00:32:54,807 --> 00:32:58,075 Are caverns and peaks the height of houses 627 00:32:58,077 --> 00:33:01,278 That churn the tides into fast, unpredictable currents 628 00:33:01,280 --> 00:33:03,680 Around alcatraz. 629 00:33:03,682 --> 00:33:06,216 Averaging just 17 feet deep, 630 00:33:06,218 --> 00:33:09,553 The tides sweep the water out towards the bridge, 631 00:33:09,555 --> 00:33:13,357 Where a perilous ravine plummets 360 feet. 632 00:33:16,829 --> 00:33:20,197 It forces 20 times more water through the narrow channel 633 00:33:20,199 --> 00:33:23,767 Than cascades over niagara falls. 634 00:33:23,769 --> 00:33:27,204 Do the inmates overcome these deadly currents, 635 00:33:27,206 --> 00:33:30,674 Or do they get washed out into the open ocean? 636 00:33:30,676 --> 00:33:34,378 Physician dr. Tom nuckton is an authority 637 00:33:34,380 --> 00:33:36,947 On swimming in the bay. 638 00:33:36,949 --> 00:33:40,851 He knows just how dangerous these waters are. 639 00:33:40,853 --> 00:33:43,653 Tom is going to use this huge scale model, 640 00:33:43,655 --> 00:33:46,223 Built by the u.S. Corps of army engineers, 641 00:33:46,225 --> 00:33:48,925 To chart the men's escape route. 642 00:33:48,927 --> 00:33:51,928 This simulator, just outside the city in sausalito, 643 00:33:51,930 --> 00:33:56,199 Replicates the currents in the entire san francisco bay. 644 00:33:56,201 --> 00:33:58,035 Nuckton: This model is really impressive. 645 00:33:58,037 --> 00:34:02,072 You can see alcatraz here, the shallow areas. 646 00:34:02,074 --> 00:34:05,342 Narrator: Tom investigates the tides around alcatraz island 647 00:34:05,344 --> 00:34:08,378 At the time of the escape. 648 00:34:08,380 --> 00:34:12,215 Nuckton: So we can put this boat... 649 00:34:12,217 --> 00:34:13,984 In the water 650 00:34:13,986 --> 00:34:17,654 Right about where we think the prisoners got in the water, 651 00:34:17,656 --> 00:34:20,090 And we can squirt a little dye. 652 00:34:23,128 --> 00:34:24,761 Okay, we have a boat that represents 653 00:34:24,763 --> 00:34:26,096 The raft of the prisoners, 654 00:34:26,098 --> 00:34:28,565 And some dye that shows the outgoing tide 655 00:34:28,567 --> 00:34:31,601 That the prisoners would have had to contend with. 656 00:34:31,603 --> 00:34:33,437 Narrator: The currents push the boat 657 00:34:33,439 --> 00:34:35,272 Towards the golden gate bridge. 658 00:34:35,274 --> 00:34:37,808 Nuckton: They'd be swept right out into the pacific ocean, 659 00:34:37,810 --> 00:34:41,211 And you can still see the dye. Look how quickly it's moving. 660 00:34:43,515 --> 00:34:46,249 Narrator: The model shows the most likely scenario -- 661 00:34:46,251 --> 00:34:51,221 The currents sweep the little raft straight out to sea. 662 00:34:51,223 --> 00:34:53,890 But these waters can be unpredictable, 663 00:34:53,892 --> 00:34:56,460 Depending on the exact time of day. 664 00:34:58,197 --> 00:35:00,864 Tom thinks there is a window of opportunity 665 00:35:00,866 --> 00:35:06,736 When a changing tide could help steer a raft to safety. 666 00:35:06,738 --> 00:35:10,373 So the san francisco bay has flood tides coming in 667 00:35:10,375 --> 00:35:12,309 And ebb tides going out. 668 00:35:14,480 --> 00:35:17,981 From this simulation, if they got in the water 669 00:35:17,983 --> 00:35:21,818 At the precisely right time, about 11:30 at night, 670 00:35:21,820 --> 00:35:25,288 They could've ridden the ebb out toward the golden gate 671 00:35:25,290 --> 00:35:28,158 And then paddled toward horseshoe bay 672 00:35:28,160 --> 00:35:30,927 In the marin headlands. 673 00:35:30,929 --> 00:35:32,896 Narrator: If frank morris and the anglin brothers 674 00:35:32,898 --> 00:35:34,731 Time it exactly right, 675 00:35:34,733 --> 00:35:38,268 They could use the shifting tides to paddle to shore. 676 00:35:40,472 --> 00:35:43,140 But tom thinks it's likely the men have to swim 677 00:35:43,142 --> 00:35:46,776 At least part of the journey. 678 00:35:46,778 --> 00:35:50,046 If that homemade raft failed, if it didn't work, 679 00:35:50,048 --> 00:35:51,314 And they ended up in the water, 680 00:35:51,316 --> 00:35:53,083 They would've been in serious trouble. 681 00:35:53,085 --> 00:35:58,155 ♪ 682 00:35:58,157 --> 00:36:01,191 Narrator: Plunging into the icy water instantly triggers 683 00:36:01,193 --> 00:36:05,328 A gasping response, drawing water into the lungs. 684 00:36:05,330 --> 00:36:07,764 You can drown instantly. 685 00:36:07,766 --> 00:36:11,034 At the same time, your blood vessels constrict, 686 00:36:11,036 --> 00:36:12,903 Pushing your heart rate up, 687 00:36:12,905 --> 00:36:17,140 Risking cardiac arrest within 2 minutes. 688 00:36:17,142 --> 00:36:19,609 If you survive that, within 10 minutes, 689 00:36:19,611 --> 00:36:21,211 The blood stops flowing 690 00:36:21,213 --> 00:36:23,880 To the muscles in your arms and legs. 691 00:36:23,882 --> 00:36:28,518 You lose coordination, and swimming becomes impossible. 692 00:36:28,520 --> 00:36:32,589 Just one in three people survive to this stage. 693 00:36:32,591 --> 00:36:35,225 After an hour, the heart slows down, 694 00:36:35,227 --> 00:36:38,728 Starving the brain of oxygen, and you pass out. 695 00:36:41,900 --> 00:36:43,767 The official report concludes 696 00:36:43,769 --> 00:36:46,970 That the men drown after their raft fails. 697 00:36:46,972 --> 00:36:50,707 The rock retains its perfect reputation, 698 00:36:50,709 --> 00:36:52,976 But the case remains open. 699 00:36:52,978 --> 00:36:57,480 Many wonder, "do the men beat the odds and survive?" 700 00:36:57,482 --> 00:37:01,585 An extraordinary discovery more than 50 years later 701 00:37:01,587 --> 00:37:03,753 Could hold the answer. 702 00:37:16,268 --> 00:37:18,034 Narrator: In 1962, 703 00:37:18,036 --> 00:37:20,570 Three prisoners set off in a makeshift raft 704 00:37:20,572 --> 00:37:24,007 From alcatraz island. 705 00:37:24,009 --> 00:37:27,811 Most investigators assume the men drowned, 706 00:37:27,813 --> 00:37:30,880 But the bodies of frank morris, john anglin, 707 00:37:30,882 --> 00:37:33,750 And his brother clarence are never found. 708 00:37:33,752 --> 00:37:37,220 57 years later, the case remains open, 709 00:37:37,222 --> 00:37:40,123 And there's one man left on the job -- 710 00:37:40,125 --> 00:37:43,226 U.S. Marshal michael dyke. 711 00:37:43,228 --> 00:37:46,529 I still get some leads called in, 712 00:37:46,531 --> 00:37:48,465 People believing they came across one of them 713 00:37:48,467 --> 00:37:51,401 Or that their next door neighbor could be one of them. 714 00:37:51,403 --> 00:37:56,306 So there's all kinds of theories that you could possibly imagine. 715 00:37:56,308 --> 00:37:58,108 Narrator: It's michael's job 716 00:37:58,110 --> 00:38:00,410 To keep an open mind about the escape. 717 00:38:00,412 --> 00:38:04,781 One theory is that the men drowned just off angel island. 718 00:38:04,783 --> 00:38:07,684 So approximately 24 hours after the, we believe, 719 00:38:07,686 --> 00:38:11,121 The escapees left the island on the night of June 12th, 720 00:38:11,123 --> 00:38:13,390 Right around the corner up over here on angel island, 721 00:38:13,392 --> 00:38:15,659 They found a paddle that was floating 722 00:38:15,661 --> 00:38:19,162 About 100 yards off the shore. 723 00:38:19,164 --> 00:38:20,664 Narrator: A homemade life jacket 724 00:38:20,666 --> 00:38:22,932 And photos belonging to the anglin brothers 725 00:38:22,934 --> 00:38:26,202 Are also discovered drifting in the bay. 726 00:38:26,204 --> 00:38:27,871 Dyke: Possibly, the escapees drowned, 727 00:38:27,873 --> 00:38:29,472 And as they were drowning, 728 00:38:29,474 --> 00:38:32,442 They discarded items just to lighten their load 729 00:38:32,444 --> 00:38:34,511 To try and swim better. 730 00:38:34,513 --> 00:38:36,012 Narrator: But another possibility 731 00:38:36,014 --> 00:38:40,183 Is that the men fake their own deaths. 732 00:38:40,185 --> 00:38:41,885 According to an accomplice, 733 00:38:41,887 --> 00:38:46,189 Angel island is where they plan to come ashore. 734 00:38:46,191 --> 00:38:47,990 Dyke: People believe the escapees 735 00:38:47,992 --> 00:38:49,426 Might've discarded these items 736 00:38:49,428 --> 00:38:51,328 To make it look like they possibly did drown, 737 00:38:51,330 --> 00:38:53,997 'cause if they were believed to be dead, 738 00:38:53,999 --> 00:38:55,332 Why keep looking for 'em? 739 00:38:55,334 --> 00:38:57,834 [ wind whistling ] 740 00:38:57,836 --> 00:39:01,438 Narrator: For more than 50 years, the trail stays cold. 741 00:39:01,440 --> 00:39:03,673 ♪ 742 00:39:03,675 --> 00:39:06,710 But in 2013, a letter sent 743 00:39:06,712 --> 00:39:08,445 To the san francisco police department 744 00:39:08,447 --> 00:39:12,382 Claims to be from john anglin himself. 745 00:39:12,384 --> 00:39:14,284 So when this letter first came out, 746 00:39:14,286 --> 00:39:16,086 A lot of us speculated 747 00:39:16,088 --> 00:39:19,189 That the escape might've been successful. 748 00:39:19,191 --> 00:39:21,991 And this letter, basically, 749 00:39:21,993 --> 00:39:25,061 Is written by someone claiming to be john anglin. 750 00:39:25,063 --> 00:39:28,098 He's claiming to be 83 years old, in bad shape. 751 00:39:28,100 --> 00:39:30,400 Narrator: The letter is intriguing. 752 00:39:30,402 --> 00:39:35,405 If genuine, it would blow this cold case wide open. 753 00:39:35,407 --> 00:39:37,674 I'm always skeptical of most of the stuff 754 00:39:37,676 --> 00:39:39,476 That comes across my desk regarding this case, 755 00:39:39,478 --> 00:39:43,046 'cause so much stuff I've seen has been made up. 756 00:39:43,048 --> 00:39:45,648 But I don't ever discount things, either. 757 00:39:45,650 --> 00:39:49,152 Narrator: Certain statements in the letter sound convincing. 758 00:39:49,154 --> 00:39:53,356 Dna and fingerprint analysis proves inconclusive, 759 00:39:53,358 --> 00:39:56,993 So fbi specialists examine the handwriting. 760 00:39:56,995 --> 00:40:00,630 Does it match that of the young john anglin? 761 00:40:00,632 --> 00:40:02,031 Dyke: Most people when they age, 762 00:40:02,033 --> 00:40:04,300 Their handwriting stays pretty much the same as it was. 763 00:40:04,302 --> 00:40:06,236 It just becomes less smooth. 764 00:40:08,240 --> 00:40:10,573 Narrator: The closer michael looks at the letter, 765 00:40:10,575 --> 00:40:13,543 The more he's convinced it's a fake. 766 00:40:13,545 --> 00:40:15,612 Dyke: So this j is absolutely nothing like the way 767 00:40:15,614 --> 00:40:19,649 John anglin writes his letter j when he writes his name down, 768 00:40:19,651 --> 00:40:21,651 'cause we have numerous examples of that. 769 00:40:21,653 --> 00:40:25,655 The phraseology doesn't match john anglin's examples. 770 00:40:25,657 --> 00:40:27,924 It's not even close. 771 00:40:27,926 --> 00:40:31,761 Narrator: For michael, the search for the truth goes on. 772 00:40:31,763 --> 00:40:34,197 It's a mystery because nobody really knows 773 00:40:34,199 --> 00:40:36,199 What happened to these guys. 774 00:40:36,201 --> 00:40:38,468 Narrator: Some believe that the escape ruins 775 00:40:38,470 --> 00:40:41,337 The rock's unblemished reputation. 776 00:40:41,339 --> 00:40:46,676 But in 1962, the prison is already living on borrowed time. 777 00:40:46,678 --> 00:40:48,511 Dyke: There's some that say it made alcatraz look bad 778 00:40:48,513 --> 00:40:50,447 Because of the escape, but at the time, 779 00:40:50,449 --> 00:40:52,549 There was already rumors among the guard staff 780 00:40:52,551 --> 00:40:55,185 That alcatraz would close probably in the near future 781 00:40:55,187 --> 00:40:56,453 Because it was so expensive 782 00:40:56,455 --> 00:41:00,657 To upgrade it to modern prison standards. 783 00:41:00,659 --> 00:41:04,060 Narrator: In 1963, a year after the escape, 784 00:41:04,062 --> 00:41:06,196 Alcatraz closes, 785 00:41:06,198 --> 00:41:12,001 Its reputation no longer able to mask its crumbling architecture. 786 00:41:12,003 --> 00:41:17,073 Today, teams work to rebuild and protect alcatraz. 787 00:41:17,075 --> 00:41:22,745 Alcatraz's greatest battle has always been with itself. 788 00:41:22,747 --> 00:41:25,849 Komas: Alcatraz island -- this is an iconic building. 789 00:41:25,851 --> 00:41:29,686 The roots of its brutal history are buried right underneath it. 790 00:41:29,688 --> 00:41:32,188 ♪ 791 00:41:32,190 --> 00:41:34,190 Narrator: For 160 years, 792 00:41:34,192 --> 00:41:37,193 Alcatraz is a jail like no other. 793 00:41:37,195 --> 00:41:41,097 During the civil war, it locks up prisoners of war. 794 00:41:41,099 --> 00:41:46,135 In the 1930s, it holds america's most wanted criminals. 795 00:41:46,137 --> 00:41:51,040 But after being hailed as escape-proof, it cannot survive. 796 00:41:51,042 --> 00:41:55,211 Alcatraz, this icon of crime and punishment, 797 00:41:55,213 --> 00:41:58,181 Is a victim of its own success. 798 00:41:58,183 --> 00:42:05,922 ♪ 799 00:42:05,924 --> 00:42:13,630 ♪ 800 00:42:13,632 --> 00:42:21,304 ♪ 801 00:42:21,306 --> 00:42:29,012 ♪