Original subtitles

- [Narrator] Spies.

- The row of alleged Russian interference

is showing no sign of abating.

- [Narrator] Covert operations.

- Russia's military forces invade Ukraine.

- [Narrator] Rumors of dark influence.

- [Newscaster] One of President Putin's critics lies dead.

- [Narrator] As the world wonders how far

Russia will go,

there's a clue in a shocking case from a decade ago,

its full story still untold.

The murder of a British citizen on British soil

using the deadliest poison known to man.

- A state-sponsored killing in London

by means of radioactivity is quite extraordinary.

- [Narrator] 10 years on, Alexander Litvinenko's killers

are still at large,

and for his family, no justice.

- Did the Russian state do it?

I'll just let the evidence speak for itself.

- [Narrator] The detectives who investigated the murder

have never before spoken.

But now they, Litvinenko's widow,

and the son he left behind

tell the inside story for the first time.

- It's not only about the investigation of crime,

it's the right story about how to be human.

- [Narrator] It's a story that reads

like a Cold War crime thriller,

but is darker than any fiction.

- [Man] This order can be given

by only one person,

President of the Russian Federation, Vladimir Putin.

(intense music)

(somber cold music)

(engines blaring)

- I remember sitting in my office

on the 15th floor of Scotland Yard,

when an officer came in and the story he told

was quite extraordinary.

There was a man lying in a hospital bed in North London

who was claiming that he was a former KGB officer,

and that he had been poisoned.

- [Narrator] The patient who had given his name

as Edwin Carter, had been admitted two weeks earlier.

- It was explained to us that Edwin Carter was

seriously ill.

They didn't know what was wrong with him.

(mysterious piano music)

- [Narrator] The patient had ulcers in his throat,

and he could not eat or drink.

He believed he had been poisoned

with a heavy metal, thallium.

- It was consistent with some of

his signs and symptoms,

so for example, he'd lost his hair,

his blood counts had dropped,

he was very anxious and seemed

very preoccupied in trying to make the point

that something illegal had been done.

(mysterious music)

- I asked whether they could guarantee

that Carter would survive

until the following morning,

and in the absence of them being able

to give us that guarantee,

I decided that we should start getting his account.

- Hello, Mr. Carter.

- [Narrator] The police started recording his interview.

He began with an astonishing claim.

- Of course at that time,

we had no way of knowing whether what

Edwin Carter was saying was true.

Can we ask you to tell us

what you think has happened to you?

- If you can imagine someone who's quite ill,

potentially hallucinating,

and then starts to tell people and unravel his story

that he's not really Edwin Carter,

he's actually a former FGB Colonel,

and he's been poisoned by Vladimir Putin's orders,

you can understand that people might've

met that suggestion with some disbelief.

- [Narrator] But Carter did offer the police

one concrete lead.

The number of a contact he claimed to of had

regular meetings with at a London bookshop.

- [Narrator] When the police called the number,

a man known only as Martin came to the hospital.

Martin, an MI6 officer, confirmed the patient

was Alexander, or Sasha, Litvinenko.

A former KGB agent now advising MI6

on Russian organized crime.

Scotland Yard realized this would be

no ordinary investigation.

- Let's try and understand why he's ill.

Let's try and get a story from him,

he was still able to talk.

Was it a criminal mystery of a medical mystery?

Find out which camp it fell into.

If it was medical mystery, nothing to do with us,

criminal, we were gonna be busy.

- I met Sasha in 1993.

Very funny, very easy talking,

very young looking, very handsome,

and very strong.

He worked under investigation

of very serious crime, but inside of Russia.

- [Narrator] After 10 years service,

Litvinenko was promoted to a highly classified unit.

- And the last thing that he was asked to do,

to kill Boris Berezovsky.

- [Narrator] An advisor to Boris Yeltsin,

Berezovsky had masterminded his reelection in 1996.

Litvinenko claimed he worked

for a secret murder squad,

tasked with Berezovsky's assassination.

- I love Sasha for feeling not to stand

if he thinks something's not right.

- [Narrator] In 1998, President Yeltsin appointed

Vladimir Putin as the Director of the KGB,

now renamed the FSB.

Litvinenko raised his concerns about

the abusive power with his new boss.

- Sasha said I'm going to see

new Director Vladimir Putin.

I said what are you going to say?

I will tell him everything what I know about corruption.

- What Sasha mentioned immediately

was very soft handshake.

- Putin took obviously opposite side.

- [Narrator] Later that year, Litvinenko and a handful

of colleagues took the extraordinary step

of blowing the whistle on state corruption

at a press conference in Moscow.

- When I ask Sasha what might happen with us

after this press conference,

he said "Marina, we have two ways,"

"One way is they will kill me,"

"and another way, they will arrest me."

(intense music)

- [Narrator] Litvinenko was arrested,

and spent over a year in jail.

In 2000, he was released, and fled the country.

(somber violin music)

- [Narrator] Despite being in great pain,

he continued to answer police questions

for more than nine hours,

over three days and nights.

- He'd never, ever asked for rest.

He just said "Just please, we need to work."

- There was a clock ticking on poor

Alexander Litvinenko's life.

The idea was for the investigators to talk to him

in as much detail, in the short time he had left to elicit

everything he knew,

because you weren't gonna get a second chance

to take a witness statement from him.

- [Narrator] Up to now, only a handful of people

had seen Alexander Litvinenko in hospital.

His wife Marina released a photo

to show the world the impact of the poisoning.

- I remember Sasha didn't like to look like that,

but in this moment Sasha said take this photo,

and I want people to see what they might do against people.

- Photographs showing his dramatic decline in health

were released this evening.

As Scotland Yard said its counter-terrorism unit

was now leading an intensive investigation.

- There's an iconic picture of Sasha as I called him.

It carries quite a lot of emotion for me,

and it did for the team at the time.

What it doesn't capture,

is it doesn't capture the incredibly suffering

that he was in.

It doesn't capture the fact that his throat

was all blistered, and you know,

he couldn't swallow, he could hardly talk.

He was in diabolical pain.

Litvinenko knew that the heavy metal thallium

was the poison of choice for the KGB.

- When he was diagnosed with this poison,

now it was like a knowledge,

to know what happened to him.

Before that, he became worse, but nobody can explain why.

- [Narrator] The problem was that though it appeared

Litvinenko had been poisoned,

no one could say exactly what with.

- We were pretty confident that it was

not going to be thallium,

that left us with nothing because

all the heavy metals that we'd looked for

which are commonly used as poisons,

the screen for those were also negative.

(mysterious instrumental music)

- [Narrator] With no medical explanation

for Litvinenko's decline,

the police sought other ways

to move the investigation forward.

- Postmortem is one of the most

valuable tools in informing murder inquiries,

and Sasha was obviously living.

And so, I wanted to do the equivalent

of a living postmortem on Sasha.

Do everything we can as if he'd died,

to try and find out have we got any puncture wounds,

look at all his samples, look at everything,

examine him head to toe,

see if we can find that trigger,

that reason that's led to his illness.

- Could a chemotherapy drug have been given to him?

Could another heavy metal have been a culprit?

And then the idea of some radioactive substance

was discussed.

- One of our experts said...

Well in Sasha's urine, we found a tiny spike of polonium,

but it's probably an anomaly in the plastic container.

Obviously we've all grown up watching James Bond,

we all know plutonium, we all know uranium, so,

I say polonium?

Don't you mean plutonium?

And so... (chuckles)

This fellow very tolerantly says no, Clive,

I mean polonium-210.

What's polonium-210?

Oh, it's the most toxic substance known to man.

Okay, how do we find out?

- [Narrator] A liter of Litvinenko's urine was sent

to the high security Atomic Weapons Establishment

at Aldermaston.

But the tests would take almost 24 hours to complete.

Meanwhile, Litvinenko's life was slipping away.

- For me it was not the end, yet.

It's still enough power to fight for his life.

He smiled to me and said...

"Rina, I love you very much."

But this time when he said it

it was just so painful because...

It looks like he said goodbye.

(somber music)

- - [Narrator] Litvinenko had been fighting the poison

for over 21 days,

and now he was sliding in and out of consciousness.

- The pumping function of his heart deteriorated,

until on the night of the 22nd he suddenly collapsed,

and went into cardiac arrest.

(loud beeping)

- The crash bell went.

When I first arrived,

somebody already started resuscitation.

So there's about probably six of us in the room.

- Time goes very slowly during cardiac arrest.

He had about 30 minutes of resuscitation.

- When we get a patient back,

it's a good moment.

You've done something right for the patient.

(somber piano music)

- [Narrator] At three PM, experts from

the Atomic Weapons Establishment called Scotland Yard

with the results of Litvinenko's urine tests.

- It was a phone call, and it's 10 years ago now,

but I could remember it like that.

"It's polonium, it's a million times a lethal dose,

"he's dead."

No, he's not dead, he's very poorly,

but he's still alive.

"No Clive, he's dead."

- Nine o'clock on the evening of the 23rd,

he suffered a further cardiac arrest.

(loud beep)

(somber music)

We're sorry to announce that Alexander Litvinenko

died at University College Hospital

at 9:21 on the 23rd of November, 2006.

- I remember it was quite a young doctor

who came to us and said...

Unfortunately we tried everything,

but your husband just passed away.

I said, can I see him?

He said yes of course, you can see him.

And when we came to his room,

Anatoly was with me.

- Every time I met my father he'd get better,

he would recover, and then quite honestly,

to me personally, when he actually died on the 23rd,

it came to me as a massive shock.

Like, until the final few days I kept thinking

that he was going to recover.

(somber string music)

- I still remember him in different way,

as very handsome.

But more important thing I could hug him in the last time,

I could kiss him, and I could feel his smile.

- We now know the former Russian spy was poisoned

by radioactive polonium,

and that is a first in the United Kingdom.

- I'd never heard of polonium-210,

I know nothing about radioactivity

or about radioactive isotopes,

but it was absolutely clear that this was

something completely out of the ordinary,

and it just changed the whole nature

of what we were dealing with.

- [Narrator] Polonium is extremely rare.

5,000 times more radioactive than radium,

and when swallowed, just one millionth of a gram

is enough to kill.

For Scotland Yard, the intensive care unit

was now a crime scene.

It was sealed off with Litvinenko's body

to protect both evidence and staff.

- Where the murder victim and the body is,

there's always a crime scene.

However, they were contaminated by polonium,

no one knew what to do,

we didn't know how safe it was.

- What we have now is a murder inquiry,

plain and simple.

You've got to stick to the facts.

Now in this case, what that transpired as being,

was following the polonium trail around London.

- [Newscaster] The places he visited

are now being searched and--

- [Other Newscaster] Three people have now been referred

to a specialist--

- [Female Newscaster] Traces of the substance

that's believed to have killed--

- [Newscaster] The risk to the public is very low.

- I remember coming out of a COBRA meeting,

and there was a whole horde of photographers

and reporters outside on the pavement,

and I remember a voice shouting at me,

"Mr. Clarke, are the public safe?"

I remember thinking to myself,

I haven't got a clue, I don't know.

- [Narrator] The polonium that killed Litvinenko

is very difficult to manufacture.

- This is something that is made in a reactor,

and therefore you have to have access

to the product of a reactor,

and the place where that is made in Russia,

is a very high security operation indeed.

So it was perfectly clear,

that was a real marker of who might be involved.

- [Narrator] Scotland Yard now had to work out

how the polonium had been brought into the UK,

and identify the assassin.

The clues were to be found in the extraordinary interview

Litvinenko had recorded just before his death.

- The focus for me was to look to see

who'd had the opportunity to poison him.

I was surprised at the presence of mind he had

as he was working through the possibilities

of the various people that he'd met

on the first of November.

He was working through it very much

with a detective's mind.

- [Narrator] Litvinenko told police

that the day he fell ill,

he met with an Italian intelligence analyst.

- [Narrator] Scaramella had sought Litvinenko's advice

for an Italian Parliamentary inquiry

into allegations that the KGB had tried to

influence the Italian government.

- I said Sasha please don't eat,

because we're going to have these special dinner.

It's the first of November,

it's already six years since we came to UK,

and it's the first time when we're British citizens.

- Sasha couldn't really understand

why the meeting was really important,

why he'd been called there,

and it flipped his suspicion radar.

(suspenseful instrumental music)

- [Narrator] Scotland Yard sent an investigation team

to Itsu restaurant.

(intense music)

- How do you search for polonium?

Well, you actually search for it with something

a bit like a Dirt Devil Hoover.

Because polonium is radioactive and it's dangerous.

It emits powerful waves.

And they only go about that far.

And so to detect them, you have to be that close to them.

(intense music)

Soon after they got in there,

I remember getting a phone call,

we got a positive indication of alpha radiation.

Itsu restaurant could be our murder venue,

we could treat as a game of Cluedo.

And that's not belittling the approach to it,

but Cluedo, you have a room, you have a killer,

you have a weapon.

And when you get those things in your envelope,

you've generally solved it.

- [Narrator] Mario Scaramella became a person of interest.

- If you're exposed to it,

what happens is is that you secrete it,

and you secrete it through sweat.

And you can't control that secretion,

so when you secret it through sweat,

in fact, when you touch something,

you pick something up, you touch something,

we can actually map where you've been.

- [Narrator] Scaramella had stayed

at the Thistle Hotel in Victoria.

(mysterious music)

- Very quickly we established

that the hotel he stayed in wasn't contaminated,

and Mr. Scaramella wasn't contaminated at all.

And so what were the chances of him being involved,

they were fairly remote.

Then why is Itsu restaurant contaminated?

The analysis when it was done,

goes to show that where Scaramella had been sitting

with Litvinenko when they had lunch

on November the 1st,

that wasn't where the contamination was found.

- Turned out that actually

it was at a different table

to the one which Scaramella and Litvinenko

had sat at on the 1st of November.

- You could've taken a view of that in the Cluedo envelope.

Itsu restaurant was the venue,

polonium was the murder weapon,

thank you very much, have a lovely day.

And then suddenly the envelope

is ripped up and thrown away.

- [Narrator] Police needed to explain

the traces of polonium on the second table at Itsu.

The clues again lay in Litvinenko's police interview.

He had another meeting the day he fell ill.

- [Police] After the restaurant, where did you go?

- When Sasha was in hospital,

and when we talk about he's suspicious

he might be poisoned, and I say but who, who could do this?

And he mentioned this meeting with Lugovoy

and Kovtun in Millennium Hotel.

(mysterious music)

- [Police] And after you drank from the pot,

did Andrei or Kovtun drink anything from that pot?

- The ingestion, eating something was important.

So, there were two screws in on this,

and if it was polonium, it would be definitive.

- [Narrator] Police turned their attention

to the hotel in Mayfair

where the two suspects stayed.

Lugovoy and Kovtun were captured on CCTV

going upstairs to the gent's toilets.

Traces of polonium were found

that matched their movements.

- So, we'll go with that the hypothesis that

Mr. Lugovoy and Mr. Kovtun,

they had more than something to do with it.

In the 16th of October,

Mr. Lugovoy and Mr. Kovtun both came into the country

on a BA flight from Moscow.

They went and stayed at the Best Western,

Shaftesbury Avenue.

Polonium was found in that room in the bathroom.

- [Narrator] Then police made their second breakthrough.

They discovered Litvinenko had an earlier meeting

with Lugovoy and Kovtun

two weeks before their afternoon tea at the Millennium.

The location?

Itsu sushi bar.

The table where they'd sat

was the one on which police had already

detected traces of polonium.

- Got contamination.

Cause it's not secondary contamination,

it was primary contamination as in

something bad had happened there.

You tried to whack him at Itsu restaurant, you tried.

(mysterious music)

So he had been attacked on the 16th.

In fact, he would've died as a result

of the attack on the 16th,

it was that significant.

But he was that robust that

it didn't work as quickly as it should have.

- [Narrator] After the Itsu attack,

Lugovoy and Kovtun travel back to Moscow

on a Transaero aircraft.

- We managed to stop them at Heathrow Airport.

That was the most raucous.

They didn't react all that well

to that plane being stopped.

(mysterious music)

- The aircraft was checked,

they did find traces of polonium-210.

In retaliation for interfering

with the Transaero flight,

the Russian authorities had placed

the tugs that pushed the aircraft back from the stands

in front of a British Airways jet at Moscow Airport.

So it's just kind of tit for tat,

that started to underpin some of the

political dimensions on this investigation.

- I think it turned out that 36,000 people

have been on planes that could've been contaminated.

- Traces of radiation found at

12 different locations including

two British Airways planes,

has an investigation stretching

right across Europe in pursuit

of a radioactive trail.

- The number of scenes that were unraveling

on a day-by-day basis,

went to about 40 odd scenes.

And this had been everything from the hotels

that the two key suspects had stayed in,

to places where they'd have meetings together.

- [Narrator] Litvinenko appeared to have survived

the Itsu attack on the 16th of October.

Lugovoy returned to London alone

nine days later.

Detectives believe he flew in armed to kill.

They found evidence in the Sheraton Park Lane Hotel.

- We came up with this random way of describing

how safe or not something could be,

and we call it the "Runaway Factor".

- The detection devices quote were "minging", unquote.

I think that meant there was a huge amount

of radiation in that room.

They had to withdraw from the room fairly quickly.

- [Narrator] Extremely high levels

of radiation in the bathroom sink and pipes

led police to believe Lugovoy had poured

the polonium down the drain.

(loud beeping)

- It was the most nuclear scene

that I think has

ever been found in civilian circumstances.

And the runaway factor there was Usain Bolt-esque.

- [Narrator] Litvinenko had ultimately died

as a result of the attack in the Millennium Hotel.

But this may have been the last of

three attempts by Lugovoy and Kovtun to kill him.

(mysterious music)

Police were desperate to prove conclusively

that Litvinenko had died from polonium poisoning.

Eight days after his death,

Britain's top pathologist finally examined the body.

- The autopsy was a difficult, dangerous procedure.

Levels of polonium that were eventually

found from the tissues,

were 100 fold higher than would be

compatible with life.

When he opened up, all you could see

is atrophy of tissue.

It's essentially sort of just

dissolved in a slurry, as it were.

And so it was clear what had been going on.

- [Narrator] The autopsy confirmed

Litvinenko's death was a direct result

of his ingesting deadly polonium.

(intense piano music)

- From fairly early on in the inquiry,

Andrei Lugovoy and Dmitry Kovtun

became people of interest,

and so that is why we wanted to

interview them as soon as possible,

and that meant sending a team of officers

to Moscow to do just that.

- In the conversation with Peter,

led to the selection of Brian Tarpey.

The formal setting for the request ops,

do you fancy going to Russia?

I think it was in the toilets on the 15th floor.

- In walked my boss, I said hello Clive,

as you would.

And his immediate response was "Ah, Tarps, my best man...

"What are you doing for the next couple of weeks"

- So obviously, the natural environment

for a challenge to be set like that.

(mysterious music)

- [Narrator] DI Brian Tarpey's team

had been briefed by MI6

about what to expect in Moscow.

- The thought of having to lead a team in Moscow

was at first quite daunting.

There was the obvious warnings

about potential honey traps.

Our rooms might be bugged, our searched.

I had left, shall we say,

certain traps which would indicate to me

that my drawers had been moved or searched.

- [Narrator] The team's first meeting

was with the Russian General Prosecutor.

- We were welcomed by the Deputy Ambassador

and the General Prosecutor.

I think there were eight objectives,

eight things that we wished to achieve

while we were there.

The top two of those would be to interview

Lugovoy and Kovtun.

It's then that the conversation

became a little more difficult.

We believed them to be in a place

called Nuclear Hospital Number Six.

He was asking what is this Nuclear Hospital Number Six,

I've never heard of it,

this means nothing to me,

you know, we don't know where they are,

we have go no idea where they are, how do you know?

- [Narrator] Nuclear Hospital Number Six

was a clinic built to treat the victims

of the Chernobyl disaster.

- About five o'clock, we received a phone call

stating, surprisingly, he was in Hospital Number Six,

and this place did exist.

(intense music)

In less than 10 minutes we were in a van.

The journey there was quite interesting.

They drove very quickly, to start with.

They didn't seem to know where they were going themselves,

and we had to, on at least two occasions,

do U-turns to get back out of the area

where we were.

Whether this was to delay us getting

to the hospital or not, I don't know.

- [Narrator] After two hours driving,

they arrived at the hospital

just before nine PM.

- The next point of contention,

we were told under no circumstances

would we be allowed to bring

any recording devices with us into the hospital.

And the interview will conclude by 10 o'clock.

- [Narrator] Kovtun was said to be

receiving treatment for exposure to polonium.

Only one Scotland Yard officer

was permitted to enter the room.

- It turned out to be a very strange

series of events.

There was a man in a bed,

who he was told was Dmitry Kovtun.

The only thing that he could see was the eyes.

It could've been anyone sat in the bed.

We'll never know who it was.

- [Narrator] After just 13 minutes,

the doctor stopped the interview.

- Of the questions that we had wanted to be asked,

only about half were asked before the time ran out.

So, it really wasn't satisfactory

from my perspective.

- To put it simply, they were messed about.

The Russians kept saying we're cooperating,

but it was unlike any cooperation

that I've ever seen.

- [Narrator] The Scotland Yard team

had been in Moscow for two days.

Developments in London were about to

have an impact on their investigation.

- Now it was being treated as a suspicious death,

but in the last hour Scotland Yard have confirmed

that they are now treating the poisoning

of Alexander Litvinenko as murder.

- The intelligence and the political

and the diplomatic dimensions

were all firmly intertwined.

And so, from a very early stage,

there was gonna be a certain amount

of finger pointing towards Russia.

- Right.

- I was concerned about the impact

of that change of status to the team in Russia.

Did it pose a challenge?

Most definitely.

You're interviewing their nationals,

and you're seeing them as a witness,

and then suddenly you've announced it's a murder.

- It must've been fairly clear

that actually a picture was unfolding,

which I fear the Russian government

would not want us to explore.

- [Narrator] After six frustrating days of waiting,

an interview with the second suspect,

Andrei Lugovoy, was canceled in short notice.

The Russians also announced that

Kovtun's health was declining rapidly.

- [News Reporter] Hours after giving evidence

to investigators in Moscow today,

Mr. Kovtun reportedly fell into a coma,

and is in a critical condition from radiation poisoning.

- [Narrator] The investigation had stalled,

and the team encountered another unexpected problem.

- I remember one evening,

my officer was complaining of stomach cramps,

and not being very well.

Earlier the next morning,

I was to accompany him back to

the General Prosecutor's office.

We were offered tea.

I had no hesitation in saying yes,

I'll have a cup of tea please.

So I had the cup of tea, and we left.

I started to feel a little uncomfortable,

and not wanting to put too fine a point of it,

I had the shits.

I have no doubt in my mind

that we were probably poisoned

with something like gastroenteritis.

I think there was a deliberate ploy

to weaken us physically,

because we were the decision makers on the team.

- It didn't stop them doing what they did,

it just meant they had to do it in short bursts.

(laughing)

- [Narrator] The following day,

Tarpey and the team were escorted back

to Hospital Number Six,

to interview the second suspect, Andrei Lugovoy.

- Again, we were told that he was a sick patient

in the hospital,

and the interviews would be conducted there.

We were told that we could not

bring any recording devices into the hospital,

so we were totally reliant

on the Russians recording this.

- [Narrator] The police were also told

the interview would be conducted in Russian,

because Lugovoy spoke no English.

- When Lugovoy was interviewed,

he looked as fit as a fiddle.

He wasn't bandaged, and was there in his own clothes,

and probably had only just

turned up at the hospital.

- I suppose I could tell you what I'd hoped for.

I hoped for an account that could give us

an opportunity to prove or disprove what they say.

- I thought that, well, this has been recorded,

so we'll get what it is that's been said,

and we can compare that to the notes

that have been taken.

At the end of the interview,

Lugovoy kind of smirked and said...

"Good luck with your investigation."

In English.

(mysterious music)

- [Narrator] After two weeks in Moscow,

the Scotland Yard detectives

were ready to return home.

All that remained was to collect copies of the evidence

from the Russian General Prosecutor.

- They agreed that they would just film the evidence

that had been handed to me.

I was presented with a bundle of interviews and tapes,

we took the evidence with us back on the flight,

back to London.

- [Narrator] The Scotland Yard team

arrived back in London the following evening.

- I was very glad to be back in the UK,

and I was equally glad to be able

to hand over a bundle of interviews, and tapes.

- [Narrator] The next day,

Tarpey received a phone call

from Scotland Yard forensics.

- It was one of the forensic management team.

He was asking was there another Lugovoy tape,

and at first I couldn't understand

what he meant by that,

and I said no, I've given you the tapes,

and I said why?

- I can't remember exactly where I was

when I found out from Tarps

that what was probably the most important

output from that whole deployment,

it never made it on the plane.

- [Narrator] The recording of Lugovoy's vital interview

was missing from the evidence package

handed over by the Russian authorities.

- I'd been outmaneuvered like a chess piece

by the Russians.

- Was it an accident?

No.

They didn't tell me that Tarps

or anyone else had been unprofessional.

It's obvi we'd been done.

- [Narrator] One month after his death,

Alexander Litvinenko's body was still so radioactive

it had to be placed in a lead-lined coffin for burial.

- It was not an ordinary coffin,

it was some from metal,

and they said if we decide one day

to take this coffin from grave,

it would be allowed only after 30 years.

- [Narrator] Alexander Litvinenko was buried

in Highgate Cemetery, he was 44 years old.

Police believe that Lugovoy and Kovtun

had poisoned Litvinenko in the Millennium Hotel, Mayfair.

But after being frustrated in Moscow,

they still needed to build a cast iron case

by proving how the polonium had been administered.

- This expert advice said that

there would be no trace of polonium

left on anything that has been washed

42 times in the dishwasher.

Don't bother doing the tea pots,

tea cups, saucers, tea spoons,

cause you'll be wasting your time.

But all the instincts were,

yeah go on, let's have a go.

(beeping)

(mysterious music)

(beeping)

It came back as a full scale deflection

on this tea pot.

Full scale deflection, so...

What does that mean?

It meant that it was a smoking tea pot.

That's not like a smoking gun,

but it was significant.

(loud beeping)

- The contamination in the tea pot

leads of course inexplicably to Kovtun and Lugovoy.

- [Narrator] The police had the last piece of the puzzle,

and handed the evidence over

to the Crown Prosecution Service.

Five months later, the CPS formally sought

the extradition of Lugovoy on a charge of murder.

- Our position was that if Lugovoy or Kovtun

left the country, and went to a jurisdiction

where they were extraditable,

we would seek to extradite them.

- [Narrator] Lugovoy and Kovtun denied the allegations

in the Russian media.

In December 2007, Lugovoy became a member

of Russia's Parliament,

giving him immunity from prosecution.

The Home Secretary, Theresa May,

ruled out a public inquiry

fearing it would damage relations with Russia.

But finally in 2014, under pressure from the High Court,

she changed her mind.

(intense music)

More than eight years after Litvinenko's death,

the public inquiry opened at the High Scout in London.

- For me it was already like, I've done it,

I'm already satisfied.

Because it was very important

to bring information to public.

- Lugovoy and Kovtun poisoned him,

and you will decide on all of the evidence

whether or not they were sponsored

by the Russian state.

- Some people started to say hm,

we're not sure they're going to do

anything against Russia,

and they say they probably will just close this case,

I'm not going to do anything.

(intense music)

- [Narrator] Finally Judge Sir Robert Owen

delivered his verdict.

- I have concluded that there is a strong probability

that when Mr. Lugovoy poisoned Mr. Litvinenko,

he did so under the direction of the FSB.

I have further concluded that the FSB operation

to kill Mr. Litvinenko was probably approved

by Mr. Patrushev, then head of the FSB,

and also by President Putin.

- It was a very powerful verdict,

it was named Putin,

and then I'm just like overwhelmed.

- It's a huge victory,

and it's a pretty remarkable victory

considering the forces that were behind

my father's murder.

- It doesn't mean Lugovoy and Kovtun

who we're certain committed this crime

are going to be sent to the prison,

but even you're not in prison,

but you're already punished.

To wake up and go to sleep to know

people knew you are criminal,

you are murder.

- [Narrator] The investigation had been

the most complex, dangerous,

and technically demanding ever undertaken

by British law enforcement.

- This was the Metropolitan Police

and police in the UK at its best.

They gave an incredible amount,

which means a huge amount to me,

it meant a huge amount for Marina,

and I couldn't be more proud of them.

- He was a real man.

He was not a double-agent, he was just a human.

And a real man is a father, is a husband.

- Good luck, take care.

- Of course, justice hasn't been done

to its fullest extent,

but you consider the situation under the circumstance

under which my father was murdered,

it was pretty amazing we got any semblance

of justice at all.

- You have this person in your heart,

you can live, but in your heart has a big hole.

I believe he's able to see everything what's happened,

and I hope he's proud of this.

(somber music)

- Marina now knows that her husband's story has been told,

and if it is disputed,

well then the people it applies to,

they can happily bowl up here

and have their day in court to explain their story.

And...

That'll be a good day out.

(mysterious music)