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00:01:00,800 --> 00:01:04,982
A mile to the west of
a hill, marked by nine

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00:01:04,983 --> 00:01:09,281
burial mounds, there
stands an old ash tree.

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00:01:13,150 --> 00:01:19,330
Her crown reaches skyward, her roots dive
deep into the land.

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00:01:24,230 --> 00:01:28,155
Many have been this
way before, passing

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00:01:28,156 --> 00:01:32,111
through the old ash and
into the world beneath.

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00:01:35,770 --> 00:01:39,050
What is this strange song that calls us
below?

7
00:01:43,420 --> 00:01:45,500
Why do we seek the void?

8
00:02:02,980 --> 00:02:06,540
Some areas of the state in the High
Sierra, strong gusts and heavy rain moving

9
00:02:06,541 --> 00:02:08,600
overhead in the latter part of the
evening.

10
00:02:08,800 --> 00:02:11,156
Travel conditions will be poor right
through to the morning.

11
00:02:11,180 --> 00:02:14,980
Meanwhile, northern areas continue to
enjoy wilder conditions than usual.

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00:05:12,000 --> 00:05:13,400
Our

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journey begins,

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00:05:22,970 --> 00:05:40,560
somewhere beneath the skin of the
earth, where darkness thickens and sounds.

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00:05:41,700 --> 00:05:42,700
Stir.

16
00:05:48,690 --> 00:05:53,133
Yet, even here, just inches
below the surface, this is a

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00:05:53,134 --> 00:06:01,350
place so alien to ours above,
where nothing is familiar

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and all is strange.

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00:07:31,440 --> 00:07:32,600
Yes?

20
00:07:33,320 --> 00:07:34,320
Yes.

21
00:07:34,400 --> 00:07:35,720
Let's go here.

22
00:07:36,620 --> 00:07:40,420
I believe in

23
00:07:50,050 --> 00:07:51,870
this region of Mexico.

24
00:07:58,970 --> 00:08:01,310
Here we have many rivers.

25
00:08:02,210 --> 00:08:03,450
Yes, yes, yes.

26
00:08:04,030 --> 00:08:05,030
Yes.

27
00:08:06,530 --> 00:08:07,530
Yes.

28
00:08:10,810 --> 00:08:11,970
Yes.

29
00:08:13,990 --> 00:08:14,390
Yes.

30
00:08:14,391 --> 00:08:15,970
I am not only fascinated by the sea.

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00:08:20,560 --> 00:08:26,240
In the early years, there was an entire
population that lived in this region.

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It was the Mayas.

33
00:08:33,010 --> 00:08:38,350
They considered the sea, as if they were
living in the world.

34
00:08:41,190 --> 00:08:43,610
The Mayas went to the sea.

35
00:08:53,540 --> 00:08:58,960
The Mayas went to the sea, and there were
many rivers in the interior.

36
00:09:19,080 --> 00:09:23,720
We always find evidence of the activities
that led to this ruin.

37
00:09:25,820 --> 00:09:33,440
Its wealth, its artifacts, all of which I
have been seeking through time.

38
00:09:37,690 --> 00:09:40,070
But in reality, we don't know what we are
going to find.

39
00:09:41,070 --> 00:09:48,230
So it is necessary to explore as much as
we can, and be prepared for what you want.

40
00:10:20,020 --> 00:10:23,080
As I descend, the first thing that hits me
is the smell.

41
00:10:24,580 --> 00:10:27,840
It's kind of a smell of a cave in the
making.

42
00:10:34,410 --> 00:10:37,930
Wet concrete and trash.

43
00:10:38,690 --> 00:10:39,690
Maybe sewage.

44
00:10:59,150 --> 00:11:05,890
You know, after years, decades,
exploring the underground, those smells

45
00:11:05,891 --> 00:11:09,210
now I completely associate with the
feeling of freedom.

46
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When you are in the main system,
all of these smaller systems dump into it.

47
00:11:28,900 --> 00:11:33,275
You wouldn't necessarily
know if it was raining on

48
00:11:33,276 --> 00:11:36,980
the surface until all of
those veins started pumping.

49
00:11:39,520 --> 00:11:44,200
And it's going to turn into a subterranean
flash flood in an instant.

50
00:12:18,610 --> 00:12:23,990
Maybe the past 20 years of my life I've
spent exploring underground spaces.

51
00:12:36,340 --> 00:12:39,580
I actually began my career in archaeology.

52
00:12:42,280 --> 00:12:45,720
Eventually, I ran into these urban
explorers.

53
00:12:47,240 --> 00:12:52,054
These incredible groups of
people who were sneaking

54
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into abandoned places
and photographing them.

55
00:12:55,880 --> 00:13:00,380
And it seemed to me like a kind of
archaeological practice.

56
00:13:01,520 --> 00:13:04,860
I feel like I was really pulled into the
underground.

57
00:13:08,640 --> 00:13:10,620
This is just now what I do.

58
00:13:20,370 --> 00:13:25,471
I guess I've made a whole career out of
writing about things that I find underground.

59
00:13:29,490 --> 00:13:33,432
As a species, our presence
on the earth extends further

60
00:13:33,433 --> 00:13:36,310
into the ground than our
buildings do into the sky.

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00:13:36,430 --> 00:13:41,530
And one day, after we've gone,
I think this will be all that's left.

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So what I want to know is, what do these
traces say about us, about humanity?

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What does it say about who we actually are
as a species?

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It's so dark in the cage.

65
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You can't see much at all.

66
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It just adds to the sense of fear.

67
00:14:48,480 --> 00:14:52,209
I mean, even for people
who go underground a lot,

68
00:14:52,210 --> 00:14:55,681
I guess, most of them never
go two kilometers down.

69
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I think even when I
was a child, I always was

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trying to make sense
of the world around me.

71
00:15:49,960 --> 00:15:52,120
My grandmother would call me Miss Y.

72
00:15:58,800 --> 00:16:01,800
I'd ask her things like, you know,
what are those stars in the sky?

73
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Why are they there?

74
00:16:02,840 --> 00:16:04,100
How was our universe born?

75
00:16:07,160 --> 00:16:08,400
Why do we exist?

76
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The answers just got thinner and thinner
until, at the end, you realize you've

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asked a question that nobody in the world
knows the answer to.

78
00:17:02,020 --> 00:17:05,097
As scientists, when we
know we need to try to look

79
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for hard things, we are
often pushed to the extremes.

80
00:17:10,160 --> 00:17:13,800
Extreme energies, or temperatures,
or distances.

81
00:17:14,760 --> 00:17:18,000
In this particular case, we're being
pushed to extreme depths.

82
00:17:22,200 --> 00:17:26,426
That's because sometimes the
experiments you want to conduct

83
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are so sensitive that you just
can't do them on the surface.

84
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There's too much interference from all the
radiation that bombards the planet.

85
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But when you're
underground, at the bottom of a

86
00:17:45,979 --> 00:17:50,581
deep mine, you can
pretty much filter all that out.

87
00:17:58,760 --> 00:18:03,780
That means that you can look for things
that you just can't see up there.

88
00:18:06,760 --> 00:18:13,360
In my case, the thing we're looking for,
if we can actually find it, would go some

89
00:18:13,361 --> 00:18:16,028
way toward answering
the question of how our

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00:18:16,029 --> 00:18:19,761
universe developed
and why we're even here.

91
00:18:23,860 --> 00:18:28,441
The only problem is, this thing we're
looking for has never been directly detected.

92
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Ever.

93
00:18:31,900 --> 00:18:37,240
So the question for me is, how do you
catch a ghost?

94
00:19:04,660 --> 00:19:09,937
Deeper we dream, far
beneath the roots of the old

95
00:19:09,938 --> 00:19:14,860
ash tree, down through
an ancient rift of stone,

96
00:19:18,540 --> 00:19:23,320
where living walls show we have long been
making these journeys below.

97
00:19:28,290 --> 00:19:36,850
Though those early human eyes encountered
simply so much darkness, since they could

98
00:19:36,851 --> 00:19:41,070
not fill that dark with light,
they filled it with story.

99
00:19:45,900 --> 00:19:52,880
In some of these stories, this world was a
perfect inversion of the human realm,

100
00:19:53,880 --> 00:19:58,700
where the feet of the dead walked soul to
soul with those of the living.

101
00:20:02,600 --> 00:20:08,640
In others, it was a place from which the
roots of a giant world tree drew its

102
00:20:08,641 --> 00:20:21,610
power, one which linked the heavens and
the earth to this land of eternal night.

103
00:21:42,680 --> 00:21:44,660
Today, we have a new environment.

104
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If we can visualize the tips of the trees
that our ancestors used to grow,

105
00:21:58,890 --> 00:22:03,450
we can always understand why we live here.

106
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For me, it is important.

107
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The Mayas are my friends.

108
00:22:32,610 --> 00:22:34,910
My family is from Cienadellos.

109
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And for this, I want to study archaeology.

110
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I want to study people with what I am
connected to.

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I am not determined, but...
This is like a... ...a preview.

112
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These are the trees that we are now.

113
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Because the work now is much faster with
this new technology.

114
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We are growing manually.

115
00:23:17,410 --> 00:23:24,310
I see that this is the distance that we
are recording.

116
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We don't know if this is the time.

117
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Do you think it can be done?

118
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Is that okay?

119
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To do what I do, descending is not enough.

120
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I need to find ways to augment my vision.

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That's when you really start to see.

122
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Sometimes in the drains, you encounter
what looks like trash.

123
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But then you look closer and you see what
it really is.

124
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People live down here.

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People who don't have homes at the
surface.

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00:25:00,890 --> 00:25:05,030
And who need to escape the heat or the
constant surveillance by police.

127
00:25:08,770 --> 00:25:10,658
You know, in cities
they often say that

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wealth rises up into
towers, into skyscrapers.

129
00:25:16,190 --> 00:25:18,750
But it's also true that poverty sinks.

130
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It sinks underground.

131
00:25:26,040 --> 00:25:29,140
Unfortunately that means that when it
rains, people die.

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00:25:58,420 --> 00:26:01,640
Part of what I do is to document stories
like these.

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To make them visible.

134
00:26:10,680 --> 00:26:14,160
The underground is full of secrets like
this.

135
00:26:21,720 --> 00:26:28,381
And documenting those secrets is the
preoccupation of a global community of people.

136
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CM HQ.

137
00:26:44,380 --> 00:26:45,440
There are no windows.

138
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People will be separated completely from
the outside world.

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19.

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00:26:51,960 --> 00:26:53,680
It doesn't look like there's some bits
left.

141
00:26:54,880 --> 00:26:57,020
1978 dating newspaper.

142
00:27:02,400 --> 00:27:09,220
But wherever we are, the drive,
the obsession of this community is about a

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00:27:09,221 --> 00:27:14,540
feeling that this stuff is just too
precious to rot in the dark.

144
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Unseen.

145
00:27:18,260 --> 00:27:21,880
So we have to do everything we can to
figure out ways to light it up.

146
00:27:22,660 --> 00:27:24,720
And to bring that back to the surface.

147
00:27:58,570 --> 00:28:02,630
These labs have to be kept incredibly
clean.

148
00:28:04,550 --> 00:28:07,522
Only the equivalent of a
teaspoon of dust is allowed

149
00:28:07,523 --> 00:28:10,830
to pass through them over
the course of an entire year.

150
00:28:14,820 --> 00:28:18,820
That's to protect all the equipment that
we have down here.

151
00:28:19,840 --> 00:28:23,360
Equipment that's helping in the search for
what we call dark matter.

152
00:28:28,720 --> 00:28:34,000
Dark matter is... well, we don't know what
dark matter is.

153
00:28:34,080 --> 00:28:35,120
That's the issue.

154
00:28:35,700 --> 00:28:38,820
As black as the midnight sky on a moon
this night.

155
00:28:40,300 --> 00:28:43,620
We think it's a substance or a material.

156
00:28:44,380 --> 00:28:48,320
Just one that we haven't been able to
detect directly.

157
00:28:50,180 --> 00:28:54,280
It's never been seen, heard, or touched.

158
00:28:55,980 --> 00:28:57,540
That's why some call it the ghost.

159
00:29:01,320 --> 00:29:05,520
The only reason we know the ghost is there
is because we can see the gravitational

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00:29:05,521 --> 00:29:09,760
effect it has on things like the motion of
galaxies.

161
00:29:13,700 --> 00:29:15,300
Even the path of light.

162
00:29:19,320 --> 00:29:23,168
That's how we've actually
been able to map how dark

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00:29:23,169 --> 00:29:26,361
matter appears to be
distributed across the universe.

164
00:29:30,800 --> 00:29:35,520
And from these maps we can see it's pretty
prevalent.

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00:29:37,880 --> 00:29:42,600
In fact it makes up around 85% of the
total mass of the universe itself.

166
00:29:48,280 --> 00:29:51,610
For someone like me that
just makes it all the more

167
00:29:51,611 --> 00:29:54,800
frustrating that we don't
actually know what it is.

168
00:30:06,920 --> 00:30:11,440
The leading theory is that it's actually
made up of particles.

169
00:30:14,480 --> 00:30:19,080
But just ones that mostly pass through
regular matter.

170
00:30:23,200 --> 00:30:27,090
But if, even if only rarely,
one of those dark matter

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00:30:27,091 --> 00:30:31,560
particles were to collide with,
say, the nucleus of an atom.

172
00:30:33,140 --> 00:30:37,060
Well that could tell us a lot about what
dark matter actually is.

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00:30:43,280 --> 00:30:47,474
The challenge is, how do
you build something that

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could catch one of those
events as it actually happens.

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In deep underground labs we've built these
massive detectors.

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00:31:38,650 --> 00:31:42,559
Some of them are more
than 15 meters across and

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00:31:42,560 --> 00:31:46,570
they sit in flooded
caverns of ultra-pure water.

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00:31:49,150 --> 00:31:54,770
Which filters out any cosmic radiation
that might have made it this far down.

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Down here only a ghost would get through.

180
00:32:01,360 --> 00:32:06,280
The hope is that if we run the right
experiment, one of these detectors,

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these giant eyes, will
see a collision between a

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dark matter particle and
something in our world.

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00:32:31,130 --> 00:32:35,410
Asking why is one of the most powerful
things we can do.

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00:32:37,210 --> 00:32:42,090
It's an act of refusing to accept a state
of not knowing.

185
00:32:46,470 --> 00:32:50,550
In some sense it's like having a load of
doors to choose from.

186
00:32:50,950 --> 00:32:53,090
You go through one and then you meet
another.

187
00:32:55,970 --> 00:32:59,263
Well I mean I think if we
open enough of these doors

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00:32:59,264 --> 00:33:01,831
then we'll actually end
up finding dark matter.

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00:33:02,930 --> 00:33:06,370
And ultimately solve one of the biggest
mysteries there is.

190
00:33:07,550 --> 00:33:08,790
The biggest whys.

191
00:33:09,810 --> 00:33:13,070
We've worked out all of the data analysis.

192
00:33:13,450 --> 00:33:16,730
So we'll be good to go with the unblinding
one at a time.

193
00:33:20,890 --> 00:33:25,157
Every time I get to do this
to actually run one of our

194
00:33:25,158 --> 00:33:28,930
experiments, I can't help but
wonder is today going to be the day?

195
00:33:30,130 --> 00:33:31,130
And the pressure?

196
00:33:33,850 --> 00:33:34,850
Great.

197
00:33:35,110 --> 00:33:36,290
Is this going to be the door?

198
00:33:45,840 --> 00:33:48,540
And then we wait.

199
00:34:03,900 --> 00:34:05,700
But it's a waiting game.

200
00:34:37,250 --> 00:34:38,250
Time.

201
00:34:39,310 --> 00:34:42,610
It flows differently in the Underland.

202
00:34:45,610 --> 00:34:49,010
Down here there are no minutes or hours.

203
00:34:49,590 --> 00:34:53,050
Only epochs and eons.

204
00:34:55,410 --> 00:34:58,050
Some call this deep time.

205
00:34:59,010 --> 00:35:04,310
The dizzy expanse of the Earth's history
that stretches away from the present.

206
00:35:12,460 --> 00:35:20,060
But for those who descend, deep time is
also another way of seeing.

207
00:35:27,490 --> 00:35:31,350
One in which things that seemed inert come
alive.

208
00:35:33,070 --> 00:35:34,850
Stone flows.

209
00:35:36,710 --> 00:35:39,190
The Earth has tides.

210
00:35:41,830 --> 00:35:43,070
And ice.

211
00:35:45,010 --> 00:35:46,090
Breathe.

212
00:36:02,380 --> 00:36:06,380
Ice itself is a recorder of deep time.

213
00:36:08,660 --> 00:36:14,260
In the frozen Underland of the cryosphere,
matter has sealed it into layers.

214
00:36:16,580 --> 00:36:20,364
Layers containing ancient
bubbles of air trapped

215
00:36:20,365 --> 00:36:23,740
at the moment of snowfall
many millennia ago.

216
00:36:47,380 --> 00:36:52,500
These deep time messengers
draw a curious view from the

217
00:36:52,501 --> 00:36:57,760
world above into icy
labyrinths carved by meltwater.

218
00:37:11,830 --> 00:37:19,730
Or downgrade tunnels of time drilled from
the surface in

219
00:37:24,940 --> 00:37:28,760
search of air that is more than a million
years old.

220
00:37:46,620 --> 00:37:50,320
Yet the deeper and older we go,

221
00:37:53,400 --> 00:37:55,020
the tighter the Earth's grip.

222
00:37:58,420 --> 00:38:02,240
And the greater its power to hold.

223
00:39:24,520 --> 00:39:28,820
But in these times, we have other
difficulties.

224
00:39:33,020 --> 00:39:35,760
There is a restriction of oxygen.

225
00:39:45,450 --> 00:39:52,311
Taking more time in these
times can result in... fatality.

226
00:40:07,950 --> 00:40:11,810
Like speleologs, everything we know is
history.

227
00:40:16,040 --> 00:40:17,180
This is the beginning.

228
00:40:18,180 --> 00:40:19,180
A

229
00:40:26,730 --> 00:40:29,050
narrow shaft 1,000 feet below the surface.

230
00:40:29,210 --> 00:40:33,250
All attempts to free the man failed and he
eventually suffocated in foul air.

231
00:40:33,390 --> 00:40:37,250
His body now to be permanently left in the
cave to avoid further risky...

232
00:40:37,251 --> 00:40:40,150
...stuck on a narrow ledge in a flooded
cave system.

233
00:40:40,290 --> 00:40:42,745
That's the situation
unfolding in Thailand right now

234
00:40:42,746 --> 00:40:45,830
where a team of young
soccer players await rescue.

235
00:40:46,030 --> 00:40:49,800
Amid the chaos, handwritten
notes passed from the boys to the

236
00:40:49,801 --> 00:40:52,930
dive team telling their parents
on the surface not to panic.

237
00:40:52,931 --> 00:40:56,221
The nine 33 men presumed
dead now found to be

238
00:40:56,222 --> 00:40:59,150
alive two weeks after
the initial collapse.

239
00:40:59,350 --> 00:41:02,098
Their survival is far
from certain as this part

240
00:41:02,099 --> 00:41:05,311
of the mine is more than
2,000 feet underground.

241
00:41:22,970 --> 00:41:24,510
And I think it's raining up there.

242
00:41:27,960 --> 00:41:28,960
We need to go.

243
00:41:29,080 --> 00:41:29,580
Right now.

244
00:41:29,581 --> 00:41:50,000
We need to go.

245
00:41:50,001 --> 00:41:52,660
I always

246
00:42:37,700 --> 00:42:42,320
ask myself, why aren't we passing so
much...

247
00:42:43,860 --> 00:42:45,400
...to do all of this?

248
00:42:46,420 --> 00:42:48,020
With only the light of the sun.

249
00:42:48,800 --> 00:42:49,840
Of the sand-torches.

250
00:42:51,240 --> 00:42:53,040
What happened if the sand-torches
disappeared?

251
00:42:55,320 --> 00:42:58,200
What was the reason why you were so
motivated?

252
00:43:26,160 --> 00:43:27,700
Being so far underground.

253
00:43:28,640 --> 00:43:30,040
You know, you don't see sunlight.

254
00:43:30,280 --> 00:43:35,920
You don't see the day-to-day motions going
on outside the window.

255
00:43:40,640 --> 00:43:44,000
And you go through all of that,
too, to answer a question.

256
00:43:47,880 --> 00:43:49,800
That answer might come.

257
00:43:52,500 --> 00:43:53,600
Or it might not.

258
00:44:01,240 --> 00:44:05,220
All this human effort, all the theory,
the engineering...

259
00:44:05,221 --> 00:44:08,220
...the hours spent underground...

260
00:44:08,840 --> 00:44:10,800
...might it all be for nothing.

261
00:46:02,440 --> 00:46:05,301
When you are in the water...
...you are going to the water.

262
00:46:07,220 --> 00:46:11,720
But you have to cross the
river of the world... ...to get to it.

263
00:46:37,080 --> 00:46:41,060
Deep in the earth, the rift turns again.

264
00:46:41,940 --> 00:46:45,140
We follow, as ancient waters gather.

265
00:46:49,520 --> 00:46:52,420
Starless rivers of myth that mark a
threshold...

266
00:46:52,920 --> 00:46:54,560
...between the worlds of the living.

267
00:46:56,320 --> 00:46:57,320
And the dead.

268
00:47:09,740 --> 00:47:14,260
Here in the Underland lie the remains of
some 60 billion humans.

269
00:47:18,490 --> 00:47:24,090
Many adorned with treasured objects to aid
their passage through the nether.

270
00:47:32,840 --> 00:47:36,940
In once dry cave systems, now flooded by
rising seas...

271
00:47:37,600 --> 00:47:41,440
...there rest bones that have not seen
sunlight for 10,000 years.

272
00:47:56,330 --> 00:47:59,270
Though we cannot know if these were tombs
to worship...

273
00:48:00,110 --> 00:48:02,070
...or ones to avoid.

274
00:48:04,990 --> 00:48:09,110
For into the earth we not only place what
we love and wish to save...

275
00:48:09,970 --> 00:48:14,650
...but also what we fear and wish to lose.

276
00:48:57,370 --> 00:49:00,530
These mines are some of the eeriest
places.

277
00:49:05,520 --> 00:49:07,020
It's so quiet.

278
00:49:09,620 --> 00:49:13,460
These voids, these mineral voids.

279
00:49:26,880 --> 00:49:31,460
Most people go underground to search for
things that are special.

280
00:49:34,000 --> 00:49:36,320
My journeys have always been a little bit
different.

281
00:49:42,860 --> 00:49:47,080
When I go underground, it's not...

282
00:49:47,081 --> 00:49:50,300
...it's not to find things that are
special necessarily...

283
00:49:50,301 --> 00:49:53,660
...but to find what we've tried to forget.

284
00:50:04,700 --> 00:50:08,580
Those things tell just as much of a story.

285
00:50:43,560 --> 00:50:47,300
Around the world we've turned so many of
these old mines into dumping grounds.

286
00:50:48,940 --> 00:50:52,200
People come to these cracks in the surface
just above...

287
00:50:52,201 --> 00:50:55,020
...and they chuck in their old cars and
broken fridges...

288
00:50:55,580 --> 00:50:57,760
...thinking, I guess, that the earth would
forget.

289
00:51:01,950 --> 00:51:04,210
But of course the earth doesn't forget.

290
00:51:08,870 --> 00:51:12,510
As a species, we've blasted our way
through the periodic table.

291
00:51:16,860 --> 00:51:20,740
We've taken all of these elements from the
earth, we've taken treasure...

292
00:51:23,380 --> 00:51:25,580
...and we've thrown it back as trash.

293
00:51:44,810 --> 00:51:47,770
But the thing is, this isn't even the
worst of it.

294
00:51:50,210 --> 00:51:54,350
There's one element that we've mined that
haunts us more than any other.

295
00:52:48,480 --> 00:52:49,480
Uranium.

296
00:52:50,060 --> 00:52:51,600
It's actually pretty hard to spot...

297
00:52:59,290 --> 00:53:01,870
...until you shine a black light on it.

298
00:53:08,100 --> 00:53:11,400
And then the uranium lights up like crazy.

299
00:53:16,030 --> 00:53:20,530
The base level of radiation in some of
these places is six times higher...

300
00:53:21,590 --> 00:53:23,530
...than the Chernobyl site is today.

301
00:53:29,000 --> 00:53:30,360
That's why I use the drone.

302
00:53:33,500 --> 00:53:36,940
So this is what I mean when I say the
underground tells a story.

303
00:53:39,740 --> 00:53:42,135
And this particular story
is about how we took

304
00:53:42,136 --> 00:53:45,301
something from the earth
and created a monster.

305
00:53:48,680 --> 00:53:51,100
And it's a monster that we now have to
contain.

306
00:53:53,640 --> 00:53:54,640
In the

307
00:53:58,990 --> 00:54:05,310
violence of celestial explosions more than
six billion years ago, uranium was born.

308
00:54:05,311 --> 00:54:06,690
Earth's

309
00:54:11,320 --> 00:54:16,280
crust is tin or tungsten, but with a force
beyond imagination.

310
00:54:18,680 --> 00:54:21,020
One which can power entire cities.

311
00:54:34,470 --> 00:54:40,150
This astonishing element we pulled from
the earth leaves another, deeper problem.

312
00:54:43,500 --> 00:54:48,780
A legacy of toxic waste that must one day
be returned to the Underland.

313
00:54:51,340 --> 00:54:55,360
Into sealed tombs designed to outlast
their makers.

314
00:54:57,880 --> 00:55:02,680
Burial sites for this the darkest material
a species has ever made.

315
00:55:38,180 --> 00:55:41,740
In this deep dark it can be hard to dream.

316
00:55:44,240 --> 00:55:47,660
To remember why we're here.

317
00:56:11,100 --> 00:56:13,680
We're going to use natural resources.

318
00:56:19,360 --> 00:56:20,960
We're going to wait until we're here.

319
00:56:21,820 --> 00:56:22,820
We're going to wait?

320
00:56:23,160 --> 00:56:24,160
Yes.

321
00:56:24,320 --> 00:56:25,760
There's a lot of water in the water.

322
00:56:27,120 --> 00:56:28,120
The water.

323
00:56:29,600 --> 00:56:32,620
We're going to analyze the formations.

324
00:56:35,880 --> 00:56:40,520
When the massive wave comes, it's
impossible to see in a day.

325
00:56:41,780 --> 00:56:42,680
We're going to wait.

326
00:56:42,681 --> 00:56:46,540
And when the wave comes, it's impossible
to see in a day.

327
00:56:47,580 --> 00:56:50,260
We have to decide for a moment.

328
00:57:01,070 --> 00:57:03,950
We believe that it's the end of the final.

329
00:57:04,690 --> 00:57:05,750
We can't see it.

330
00:57:24,700 --> 00:57:25,700
Fatima?

331
00:57:25,880 --> 00:57:25,980
What?

332
00:57:26,860 --> 00:57:28,440
Do you feel it's the end of the wave?

333
00:57:28,920 --> 00:57:30,200
No, because we're going to wait.

334
00:57:32,780 --> 00:57:34,620
We're going to wait.

335
00:57:35,700 --> 00:57:36,340
Jose?

336
00:57:36,341 --> 00:57:37,341
Jose.

337
00:57:38,380 --> 00:57:40,340
But no, no...

338
00:57:41,600 --> 00:57:42,600
It's Felix who's talking.

339
00:57:43,480 --> 00:57:44,480
Don't you know?

340
00:57:58,480 --> 00:58:03,740
The people who have when I'm in the water
don't know what people have in the water.

341
00:58:10,310 --> 00:58:12,050
I'm in need of these people.

342
00:58:18,120 --> 00:58:19,450
I'm in the water.

343
00:58:20,920 --> 00:58:22,760
Every day I'm in the water.

344
00:58:26,100 --> 00:58:32,220
For Fatima and me, I'm in the water
through the water.

345
00:58:33,200 --> 00:58:36,160
The color of my soul is in the water.

346
00:58:42,100 --> 00:58:43,100
So...

347
00:58:55,820 --> 00:58:57,310
I want to solve it.

348
00:59:01,830 --> 00:59:02,830
But I can't.

349
00:59:08,660 --> 00:59:09,660
We are together.

350
00:59:15,730 --> 00:59:18,090
More profoundly in the water.

351
00:59:34,760 --> 00:59:39,780
The wave of a rat I don't know what it's
doing.

352
00:59:47,960 --> 00:59:49,540
I don't know what it's doing.

353
00:59:58,150 --> 01:00:49,490
Ah, okay.

354
01:00:53,310 --> 01:00:54,430
Should we start again?

355
01:01:01,240 --> 01:01:06,227
When an experiment
doesn't end up finding dark

356
01:01:06,228 --> 01:01:10,721
matter, you know, it
can be really frustrating.

357
01:01:13,380 --> 01:01:16,280
You sort of ask yourself, are we ever
going to find it?

358
01:01:20,010 --> 01:01:23,750
The experiments can run for months,
sometimes even years.

359
01:01:26,870 --> 01:01:32,370
We keep tweaking the parameters for them
to look in as many ways as they can.

360
01:01:34,470 --> 01:01:37,842
After a certain point,
if they continue to

361
01:01:37,843 --> 01:01:42,591
return null results,
then it will be shut down.

362
01:01:43,950 --> 01:01:48,340
And then at that point, as a community,
we need to decide where to explore next.

363
01:01:50,210 --> 01:01:52,330
The ones that are using DAS targets,
right?

364
01:01:53,250 --> 01:01:57,030
Is it because it's easier to identify the
beginning and end of the track?

365
01:01:58,890 --> 01:02:00,810
But there are plenty of other experiments
to run.

366
01:02:02,210 --> 01:02:03,210
Many doors.

367
01:02:04,070 --> 01:02:09,370
We just have to keep opening them until
there's nowhere left to look.

368
01:02:26,040 --> 01:02:27,040
Exactly.

369
01:02:34,240 --> 01:02:35,240
Ah, the windows!

370
01:02:36,540 --> 01:02:37,540
Yes, the windows.

371
01:02:38,200 --> 01:02:39,200
Stephanie.

372
01:02:39,340 --> 01:02:40,800
Yes, wow!

373
01:02:43,660 --> 01:02:44,900
Yes, I see what the windows do.

374
01:02:44,980 --> 01:02:45,260
The windows?

375
01:02:45,640 --> 01:02:46,640
Yes, they do.

376
01:02:47,300 --> 01:02:48,300
Yes.

377
01:02:50,420 --> 01:02:51,680
Are the windows open?

378
01:02:52,880 --> 01:02:53,880
No.

379
01:02:54,580 --> 01:02:55,640
I don't think so.

380
01:03:01,620 --> 01:03:09,080
Many times in the region, nobody has ever
seen something like this.

381
01:03:13,370 --> 01:03:15,070
Even with different materials.

382
01:03:17,470 --> 01:03:18,050
Very nice.

383
01:03:18,250 --> 01:03:18,790
Thank you very much.

384
01:03:19,230 --> 01:03:23,250
Thank you very much.

385
01:03:23,270 --> 01:03:27,970
We're going to use carbon particles and
we're going to use them.

386
01:03:28,210 --> 01:03:29,210
Yes?

387
01:03:30,650 --> 01:03:36,390
Ten years ago, with the days, with the
months, with the months,

388
01:03:40,060 --> 01:03:48,580
the coloration, the coloration, it's very
probable that carbon is being pulverized.

389
01:03:50,200 --> 01:03:51,480
Are you going to use your hands?

390
01:04:24,100 --> 01:04:25,500
Yes.

391
01:04:53,150 --> 01:04:54,270
Very good.

392
01:04:54,850 --> 01:04:55,850
Very good.

393
01:04:56,250 --> 01:04:57,250
Uh-huh.

394
01:04:57,550 --> 01:04:58,590
You can use your hands.

395
01:04:59,190 --> 01:05:00,190
Like you don't want to?

396
01:05:00,430 --> 01:05:00,650
Yes.

397
01:05:01,310 --> 01:05:02,310
You can use your hands.

398
01:05:03,110 --> 01:05:03,410
More or less.

399
01:05:03,970 --> 01:05:04,970
More or less.

400
01:05:18,820 --> 01:05:21,340
I'm going to use my hands right now.

401
01:05:38,140 --> 01:05:39,620
Ah, look at that!

402
01:05:41,860 --> 01:05:43,260
Look at that!

403
01:05:43,320 --> 01:05:44,320
Look at that!

404
01:05:44,820 --> 01:05:45,820
Look at that!

405
01:05:59,280 --> 01:06:00,340
Look at the sea.

406
01:06:01,960 --> 01:06:07,600
I thought, it's difficult to find this
place for my ancestors.

407
01:06:09,680 --> 01:06:17,320
For this, here, the Mayans decided to use
this sea as a special place.

408
01:06:18,880 --> 01:06:22,120
We are talking about a sea of
Uso-Cotitiano.

409
01:06:22,480 --> 01:06:24,520
We are talking about a sea of ritual.

410
01:06:26,500 --> 01:06:29,340
We are talking about a sacred space.

411
01:06:51,420 --> 01:06:56,000
Here, at our deepest point, stone folds.

412
01:06:57,740 --> 01:06:58,760
The rift ends.

413
01:07:01,920 --> 01:07:03,740
We can go no further.

414
01:07:12,360 --> 01:07:18,680
Our oldest and most treasured stories are
of descents made into the earth.

415
01:07:19,960 --> 01:07:25,860
Of those who answered the call of a
strange song that beckoned them downward.

416
01:07:27,400 --> 01:07:31,800
To this place of secrets, lost to the
dark.

417
01:07:35,180 --> 01:07:38,880
Though now, it is the surface that sings.

418
01:07:40,740 --> 01:07:45,340
That strange and sunlit overworld.

419
01:07:50,300 --> 01:07:55,839
I've definitely thought
about what it would be like if

420
01:07:55,840 --> 01:07:59,200
the answers never came
over the course of my lifetime.

421
01:08:05,360 --> 01:08:09,820
And I've come to terms with that as a very
realistic possibility.

422
01:08:18,020 --> 01:08:22,940
The first person to discover dark matter
might be someone out there right now.

423
01:08:24,360 --> 01:08:27,628
Maybe some little girl
looking up at the night

424
01:08:27,629 --> 01:08:31,161
sky, bugging her grandma
by always asking why.

425
01:08:47,520 --> 01:08:52,100
Every time I venture into the underground
and witness the things that we've left

426
01:08:52,101 --> 01:08:58,140
down here, I can't help but imagine some
future civilization exhuming this stuff,

427
01:08:58,400 --> 01:09:01,240
studying this stuff, and therefore
studying us.

428
01:09:07,620 --> 01:09:12,460
Sometimes I even imagine myself as this
future archaeologist.

429
01:09:16,280 --> 01:09:24,380
Thousands of years from now, I imagine
finding a sign in the earth warning me of

430
01:09:24,381 --> 01:09:27,200
what's buried there, telling me not to dig
it up.

431
01:09:32,780 --> 01:09:37,980
These signs are things we're actually
making now, in the present.

432
01:09:44,220 --> 01:09:48,980
And of course, on one level, it's,
it's horrific.

433
01:09:49,980 --> 01:09:54,440
But the fact that we're thinking about the
well-being of future generations,

434
01:09:54,441 --> 01:10:01,820
maybe even in 10,000 years, gives me hope
that humanity has, has some care.

435
01:10:03,880 --> 01:10:06,867
And you see there a
possibility of, of moving beyond

436
01:10:06,868 --> 01:10:09,300
just thinking about ourselves
or the next generation.

437
01:10:09,480 --> 01:10:10,630
We move into deep time.

438
01:10:13,400 --> 01:10:19,920
A space where we can imagine ourselves as
ancestors.

439
01:10:46,740 --> 01:10:52,920
I'm going to begin to understand what I
want to express my past experiences.

440
01:10:57,800 --> 01:10:59,300
Everything is interconnected.

441
01:11:05,980 --> 01:11:07,480
Everything is interconnected.

442
01:14:44,480 --> 01:14:57,080
Out to the island on the horizon following
the path of the sun

443
01:15:01,920 --> 01:15:05,400
following the path of the sun

444
01:15:12,440 --> 01:15:30,760
Over the sandbar holding the North Star
Steady between must and spark Creek of the

445
01:15:30,761 --> 01:15:48,420
old and town of the hour It was keeping
watch for the power, watch for the waves,

446
01:15:48,820 --> 01:15:53,660
breath, watch for the moon's death.

447
01:15:54,540 --> 01:15:59,360
Down in the waters of day.

448
01:16:01,660 --> 01:16:07,480
Fairy man, fairy man, carry my memory on.

449
01:16:08,560 --> 01:16:16,540
Out to the island, on the horizon.

450
01:16:17,560 --> 01:16:20,940
Following the path of the sun.

451
01:16:25,580 --> 01:16:29,580
Following the path of the sun.

452
01:16:34,750 --> 01:16:43,330
For the stone ones are broken,
my sadness is woken.

453
01:16:44,890 --> 01:16:49,670
Sea roads are mistaken.

454
01:16:51,490 --> 01:16:58,970
So stung by the aviation forces.

455
01:17:00,890 --> 01:17:05,830
If we grow weak and frail.

456
01:17:08,310 --> 01:17:15,950
And with arms made of granite and a blaze
of gannets.

457
01:17:15,951 --> 01:17:23,210
We broke this planet.

458
01:17:25,670 --> 01:17:31,130
Fairy man, fairy man, carry my memory on.

459
01:17:32,750 --> 01:17:43,960
Out to the island,
on the horizon.

460
01:17:43,961 --> 01:17:52,690
Following the path of the sun.

461
01:18:33,910 --> 01:18:43,510
Fairy man, fairy man,
carry my memory on.