Original subtitles

We've all seen James Bond.

The question is, what will it be like?

Will I be asked to kill people? How dangerous will it be?

Most people live in blissful ignorance

of what goes on around them.

It's a spy's job to keep it that way.

I believe till last moment he will recover.

But his heart stopped at the end.

When an intelligence officer is recruiting a spy,

they think of the acronym MICE:

money, ideology, coercion, ego.

Other members of MI6 just don't believe he could possibly be a spy.

Were you, in fact, the third man? No, I was not.

Can you imagine waking up and worrying you might have

said something that would give you away as a traitor?

I heard the voice menacingly uttering these words,

"We know who you are. We know who you're working for. It's over."

The world of espionage is all around us.

It's an unseen world. Operations are playing out all the time.

Narratives we never see or hear.

Deceit and manipulation are... are hard-wired into the profession.

If you can persuade the enemy

that you're approaching from the right flank

rather than the left flank,

then you're going to be able to achieve surprise.

We have to maintain the deceit, because typically,

you're operating in hostile environments.

If you are caught, then the results could be catastrophic.

The absolute bedrock of any intelligence service is deception.

If you're going to work secretly,

you've got to mislead the other side. They mustn't see you coming.

What you need to do is to feed your story to the adversary

through as many channels as possible.

So they begin to believe, "Well, it must be true."

AIR-RAID SIREN BLARES

MORSE CODE MACHINE BLEEPS

My father was a German double agent,

sending information to the German secret services.

He actually worked for the American Army as a liaison officer,

just outside west London. And so he was on the radio,

supplying information to the Germans.

As we got closer and closer to the D-Day landings,

he was reporting on gatherings of troops

and gatherings of senior military officials.

Really detailed, er, war plans about the build-up of troops

that were clearly gonna be landing at Calais.

These troops were assembling,

in anticipation of a major move across the English Channel.

The extraordinary fact is that that was completely fictitious.

The job never existed.

And my father was giving created information

as part of a bigger picture to divert attention away

from the real landings that were gonna take place in Normandy.

With Double Cross, the idea was to run double agents

against Nazi Germany,

and in many cases, for the Germans to think

that they were really their own agents.

It took a particular kind of fiendish intelligence, I think,

to feed material back to the Germans in order to deceive them.

It's about persuading the Germans that we're going to attack

not in Normandy, but in Calais.

It's a long, slow deception

of gradually feeding pieces of intelligence, information,

to the Germans ahead of the landing on the beaches of D-Day.

My father was a case officer,

which meant that he had charge of the double agent,

and was responsible for coordinating the information

that they sent back to Germany.

There were some ground rules.

All of the messages sent out by the double agents

were coordinated

because it was vital that not one agent tripped another agent.

The people running this operation

are effectively conducting an orchestra,

and there are different instruments in this orchestra.

In some cases, it's spies who are sending back false information.

In other cases, it's physical things. It's entire phoney armies.

WEST: You'll be able to look and see aircraft and gliders,

landing craft, in river estuaries.

What they weren't aware of

were the tanks were dummy rubber, blow-up tanks.

The landing craft were made of balsa wood.

And many of the aircraft were dummy aircraft

concentrated on airfields in the southeast of England

and East Anglia.

Because that would clearly be the launch point for an attack

across to the Pas de Calais.

It's difficult these days to imagine anything so complex working.

There's great risk with deception

that if the adversary sees through it,

then you've actually given them the one thing

that you were trying to avoid, which is your true intentions.

GERRY: It was desperately important

that the potential build-up of German troops

were diverted away from Normandy,

because otherwise D-Day would stop pretty much dead in its tracks.

MORSE CODE MACHINE BEEPS

And so, agents like my father

carried on sending and transmitting information

that the invasion of Calais was to take place.

SUSTAINED GUNFIRE AND EXPLOSIONS

The German High Command

was convinced by clever multiple deceptions.

They held back a whole German armoured division.

And that may well have saved the Normandy landings,

cos if that armoured division had been opposing the landings,

then it could all have ended very, very badly.

ALDRICH: So this is deception on a massive scale,

and it's so effective

that even after the Allies have landed in Normandy,

the Germans believe that the real attack is a fake.

They believe the deception story so completely.

CHUCKLING: They even continue to believe it

once the allies have landed after D-Day.

It's a remarkable achievement.

Double Cross is not just one of the great operations

of the Second World War,

but it was one of the greatest deception successes in history.

I'm proud of my father. It's an extraordinary achievement.

It's what intelligence has morphed into in the 21st century,

is by and large is the offspring

of the success of the Double Cross system in the Second World War.

There will be thousands of my father's equivalents

wandering the streets of London or Kabul.

So it's kind of, yeah, the game goes on.

MI6 isn't a building full of spies.

It's a building full of intelligence officers.

Intelligence officers recruit agents.

Those agents are the spies that are in their organisations.

An agent is a person who's outside of an intelligence agency.

They're a normal person going about their normal lives,

and they would be approached and recruited

by someone who works for an intelligence agency.

In the UK, we call this person an officer.

And the idea is that every officer should have a range of agents.

A web of agents, if you like, who report on their various targets.

If you can recruit somebody in the enemy organization,

you are effectively crippling your enemy.

And that's what really does damage.

That's the really big win in intelligence circles.

I remember, as a senior military intelligence officer,

reading reports that had come from MI6.

And it was clear from what was being said in those reports

that they had someone inside Al-Qaeda.

One thing you should know about espionage, as well as bomb-making,

the first mistake is your last mistake.

You're not going to live to make another mistake.

RAPID GUNFIRE

He realised that Al-Qaeda were targeting non-combatants,

civilian targets, targeting other Muslims, and killing more Muslims.

That was when it was very clear in his mind,

that's not what he signed up for.

I made the conscious decision to leave, and through some...

you know, some incredible circumstances,

I ended up in the lap of the British intelligence.

That is probably one of the bravest things that he has done,

and it's a mark of how he was trusted

within the Al-Qaeda organisation that he managed to do that.

When you're a spy, you have to really convince yourself

that you are a genuine West-hating, bloodthirsty jihadist,

and you have no qualms whatsoever

about killing all of those who stand in our way.

Every time Aimen will have come out to be debriefed,

they'll have had to make sure that he wasn't compromised.

So that when they do put him back in again,

he won't be arrested by them, tortured, and then killed.

Your task is to absorb everything around you.

You are learning about the camps, locations,

the number of people attending, the names, aliases.

You spend literally, you know, hundreds of hours

reconstructing it again

for the benefit of the intelligence services.

MI6 would provide training to an agent it recruits

about how to be aware of any risk or danger to themselves,

but a lot of times, these agents have to rely on their own wits.

I remember in 1999, in one of the camps, I was in the kitchen.

I distinctly felt the end of a pistol against my spine.

I heard the voice of one of our fellow jihadists in the camp.

"We know who you are, we know who you're working for. It's over."

One wrong word and you are a head shorter and six feet under.

So I told him, in no uncertain terms, "Lower your weapon.

"It is explicitly forbidden to point a gun at a fellow jihadist.

"And I won't tolerate this joke."

It's not an uncommon practice among different organisations

whenever they know they've got a mole somewhere.

They'll do things to shock people and watch what their reaction is,

and this was clearly designed to shock him.

After he left the kitchen,

even though it was November, in Afghanistan,

it was starting to snow,

you know, I was sweating buckets.

It's a mark of the strength of his character

that in that sort of situation, he didn't panic

and give away indicators

to suggest that he was the mole, he was the agent.

Life in the University of Cambridge in the 1930s was very exclusive,

publicly-educated men would be part of a quite intimate circle

that was also quite arrogant.

These are clever people. They can see what's happening in Germany.

They can see what's happening in Italy. And they don't like it.

Who are the people who are resisting fascism in the mid-1930s?

It's the communists.

Communism is seen as the answer,

but it's not necessarily seen as in conflict, surprisingly,

with being British.

The Soviet Union had decided on a new policy

that they would target undergraduates

at the best universities

who were likely to go on to good jobs.

They're saying to their recruits "Just stay in the background,

"go into Whitehall, go into Westminster, go into politics.

"In the future, you're going to be useful to us."

He was won over by the cause, not as a concept or an ideology,

but as an action that he could take.

He was young and he was impassioned

and he felt like he could change the world.

Kim went to Westminster, he went to Cambridge,

he was part of that upper-class, British, stiff-upper-lip,

"don't dwell too much on your emotions,

"certain things we never talk about."

So you sort of compartmentalise.

And it sort of breeds an ability to keep secrets.

I think he walked between these two worlds. There was this secret life.

You learn to hide your feelings to, in a sense, play the game,

and you become a chameleon.

NEWSREEL: 'The government's final warning to Hitler has been ignored

'and a state of war once more exists between Great Britain and Germany.'

The Russians were very keen for their recruits

to take a whole variety of jobs.

They clearly targeted all sorts of organisations,

but of course, intelligence services were part of that.

There wasn't time to do checks.

And in those days, it was assumed if you'd been to the right school,

that you would be fine.

Mr Lyubimov, could you give your full name please?

Well, it's Lyubimov Mikhail Petrovic.

I entered the KGB in 1959.

I was sent to Great Britain in 1961,

and worked there until '65.

Kim Philby was a very charming man.

To discover such a person is not so easy.

He was from the establishment.

He was a son of a very important man, a scientist,

and he was closely connected to the British high circles.

And of course, he was trusted.

Philby was, I think, the most successful

at leading that double life,

working his way inside the British Secret Service.

It's sort of a bit of a boys' club.

They all had parents who knew one another,

they all were part of the same elite establishment.

Philby climbs higher and higher within MI6.

And he's ultimately where he wanted to be, head of Section IX.

Ironically, in charge of the Russian desk.

The Russians couldn't believe their luck.

It would've given them a very, very clear advantage

in this crucial moment in the Cold War.

CHARLOTTE PHILBY: It was him who was responsible for keeping tabs

on what they had on the Soviets.

It's something that if you did write it in a novel,

people would think that it was too far-fetched.

When I was operating under alias, I was that person,

there was no question about it. I was not Matthew Dunn.

It is like acting.

Obviously the difference being at the end of a performance,

the actor takes his or her costume off and that's it.

Whereas as intelligence officer, you're living that role

for however long the operation lasts.

HARRY FERGUSON: If you were an officer who was going abroad

as a businessman, you would spend some time shadowing a salesman,

learning the lingo. You've got to be convincing in that role.

And you've actually got to do some of that work.

You are out there undercover, fake identity.

And having to be eternally vigilant does take its wear and tear.

It takes its toll.

At peak, I had 14 aliases.

It's not just a case of having a passport, a credit card...

One has to have a whole life behind that name.

So that would include things like

knowing which schools you've been to, the names of your teachers,

what beer is on draft in your local pub,

what your local cinema is.

The whole backstory. So you have to have answers ready to hand,

in case you get caught out.

Peter and Helen Kroger ran an antiquarian book shop in London,

they lived at Cranley Drive in Ruislip.

They had slightly unusual accents. But to all intents and purposes,

they looked like entirely normal people in the suburbs.

They had a car, they made friends with all the neighbours.

Helen Kroger made a point of having children's parties

and inviting the local neighbours around.

They seemed like an ordinary, if foreign couple

living in that suburban environment.

But there was much more to Peter and Helen Kroger than first met the eye.

NEWSREEL: Ready for her launching and to be given a famous name

at Barrow-in-Furness, a revolutionary ship.

The Royal Navy's first nuclear-powered submarine.

In 1960, Britain was launching the first nuclear submarine

which the United Kingdom had.

I name this ship Dreadnought.

May God bless her and all who sail in her.

Now, Britain was developing a world-beating sonar

for this submarine down at Portland,

the centre of all Britain's, and a lot of NATO research,

into everything secret about underwater warfare.

The KGB had two spies operating inside Portland.

One was a man called Harry Houghton,

and the other was his mistress, called Ethel Gee.

PHONE RINGS

My father was in counter-intelligence.

He had a lot of charm, managed to get people to cooperate

by sympathising with their position, you know,

not just simply telling them they jolly well had to cooperate.

One of the things that my father really didn't like

was he didn't like people pretending to be something they weren't.

MI5 set a surveillance team onto Harry Houghton.

And he came up to London with his girlfriend, Ethel Gee.

And he met, outside the Old Vic, a mysterious man.

And MI5 discovered his name was Gordon Lonsdale.

And the early evidence suggested he was a Canadian businessman.

NEWSREEL: They found that he was certainly in business,

associated with some small companies

operating from the second floor

of number 19 Wardour Street in the West End.

The seedy characters of Harry Houghton

and then Gordon Lonsdale, who lived in Soho in the '60s.

These were, kind of, characters

which you almost couldn't make up now,

but were very much of their time.

Elwell took the top off and discovered, hidden in the bottom,

one-time encoding pads, which were the trademark of the KGB.

There was this moment of realisation by MI5 that they had on their hands

a top KGB spy.

He clearly was a very sophisticated operator.

I mean, brilliant, actually, when you think about it.

My father did have great sensitivity as an investigator.

He had this ability to put himself into Gordon Lonsdale's mind.

Peter and Helen Kroger weren't Peter and Helen Kroger at all.

Their real identity was Lona and Morris Cohen,

and these were top KGB spies

who were recruited by the KGB at the end of the 1930s.

Gordon Lonsdale was their controller, and he, on the one hand,

dealt with Harry Houghton and Ethel Gee

and collected the material from them.

And then he took it over to the Krogers.

The Krogers would send the material to Moscow by means of microdots.

So this is about using sophisticated filming to reduce documents down,

really, to the size of a pinhead.

This is 1960s advanced spy technology.

And because Peter Kroger was an antiquarian book seller,

he would replace the full stops... Think of it, just the full stop,

with a photograph of a secret document.

So when the trial took place,

there was massive international publicity about it.

People could not believe the idea

that antiquarian book sellers living in Ruislip

might have been running a spy base out of their home,

and it did give rise to that question,

"Well, who else might be a spy? Who else next door might be a spy?"

And so this kind of spy fever certainly takes hold in the '60s,

and there's talk of spies and traitors and deception everywhere.

It sounds like fiction, but it's fact. It happened here.

NEWSREEL: The Brandenburg Gate in Berlin was once as proud a landmark

as the Arc de Triomphe.

Now it marks the dividing line between East and West.

Between the two parts of Berlin.

A lot of the spy fiction that we love mirrors reality,

and often written by those that were intelligence officers.

They've inhabited that world, they understand it,

so that fact and fiction just blurs.

I had an obsession with authenticity,

or the search for authenticity,

and that made me, well, frankly,

travel to almost all the places I mentioned in the books.

That derived, really, from The Day Of The Jackal.

I wanted to see the real thing.

If you're going into that world at all, absolutely vital

that you have a cover story,

and the best cover story of them all is true.

I was a foreign correspondent in East Germany,

who legitimately asks questions and reports back,

supposedly to his editor,

but maybe to someone else, apart from the editor.

I knew my office was bugged. My bedroom was bugged.

My sitting room was bugged.

And whenever I went out onto the street, there they were behind me.

I could just stay in East Germany

for three, four, five, six days at a time.

And while there, I could do whatever was wanted,

deliver a message, pick up a message, observe and report back.

Because David Cornwell was a serving intelligence officer,

he decided that he needed a pseudonym.

So he adopted the pseudonym John Le Carre.

John Le Carre, of course,

specialised in books about deception, dissimulation.

Um, pretending not to be what you are and to be what you're not,

and getting away it.

He made occasional trips into Berlin,

which was then an island inside East Germany,

and he found out that the East Germans

were erecting a wall dividing the city in half.

And it became the dominant symbol of John Le Carre's breakthrough novel,

The Spy Who Came In From The Cold.

It was one of the last major feature films made in black and white,

and it was deliberately done

in order to give a sense of the, kind of, bleakness of the Cold War.

Everything was grey and dark.

SIREN BLARES

Halt! Halt!

GUNFIRE

Prior to that, it was assumed that all espionage was just gentlemen,

all public school, all jolly good chaps.

John Le Carre was the first to say, "No, it's not like that at all.

"It's down there, dark and devious and mucky,

"and involving treachery and betrayal."

What the hell do you think spies are?

Moral philosophers measuring everything they do

against the word of God or Karl Marx?

They're not. They're just a bunch of seedy, squalid bastards like me.

But the real world of espionage is about deception,

and sometimes the horrible penalties of failure to deceive -

being caught.

You bury your nervousness so deep

in order to make sure that it doesn't show.

From dawn all the way until mid-afternoon,

that is where we are experimenting

and blowing up new kind of explosives,

or testing, you know, the latest batch

of poisons or chemical weapons.

Al-Qaeda were very interested in particularly chemical weapons

and did a lot of work in Afghanistan

trying to produce a small, compact, viable, chemical

improvised explosive device

that could be used to kill and maim people.

These are bombs, or chemical gas devices

to be left on trains, insides cinemas, nightclubs.

There are no civilians as far as our enemies are concerned.

A chemical bomb or a biological bomb going off on the New York Subway

or the UK Underground would have a devastating impact.

Whenever agents come across nuggets of information, like Aimen did,

that's when you get something that is so important to get out,

especially if it's... if there's a timeliness attached to it,

the agent will take additional risks to get the information out

so they can try and stop the attack.

If you are nervous, it'll show.

The first mistake is your last mistake.

You're not going to live to make another mistake,

and therefore, you have to be absolutely careful.

If he got caught, he would've been tortured

for as long as they could have tortured him for,

and then killed in a very, very painful and extreme way.

We're looking at a rucksack-sized device, you know,

maybe a couple of kilos.

Now, in the confines of an underground train,

we're talking five or six people may be killed by the explosion.

But hundreds killed by the panic.

If you've got a thousand people on a Tube train

and everybody's trying to get out at the same time, at the full sprint,

one can imagine how horrific that would be.

Aimen was lucky.

He didn't blow his cover, and managed to get the information out

in a timely way that allowed the attack to be intercepted.

The role of double agents, the role of people like Aimen,

was fundamental.

Without people who are prepared to do the most dangerous things,

and take the most heinous risks,

we would be a lot less safe in our beds here in the UK.

When Philby was posted to Washington,

it expanded his access dramatically.

Cos it gives you access to the FBI and the CIA.

He's a star British intelligence officer.

He's at the height of his game.

He's being groomed to be head of MI6.

He's at the centre of this whole operation,

whilst passing not only British intelligence,

but intelligence which the Americans are sharing with us.

That's also being sent to the Russians.

He was obviously calculating, but he was also opportunistic.

And I think that's to do with personality.

That's just fundamentally about being able to charm

and persuade people that you are the version of yourself

that you want them to see.

The Cambridge Five were in the Cabinet Office in Bletchley Park,

in MI6, MI5, they had agents everywhere.

It was so lax, the security,

that they were able to just, with impunity, go in and out

and remove literally thousands and thousands of documents.

LYUBIMOV: These Magnificent Five,

they're unique in the history of espionage.

They supplied the information about all the talks in the Cabinet,

all the Cabinet papers.

So it was such an amount of information.

CORERA: This was a cosy establishment club

of people who were friends and knew each other,

and who covered for each other.

LOWNIE: There were suspicions about them.

The problem was they were never really followed up.

No-one wanted people to report on each other,

because it was sort of like school. It was telling tales.

So there were a lot of close calls.

Very gradually, very slowly,

Western code breakers start to make some inroads.

Not very much, but enough to identify some of these agents.

Suspicion starts to fall

on the fact that there might be a spy in Washington.

And they point to the fact that there'd been a spy

in the British Embassy in Washington,

and suspicion eventually falls on Donald Maclean,

one of the Cambridge Five.

They were worried, they were under surveillance,

they were being bugged. And the escape plan was put into operation.

It captured people's imagination.

I mean, people love spy films, and this wilderness of mirrors,

of trying to work out what's really going on.

There was a real worry that we were on the point of another war.

Now the cracks are beginning to appear, and for Philby,

the attention turns to him as a possible third man.

If there was a third man, were you, in fact, the third man?

No, I was not.

Do you think there was one? No comment.

Why didn't he run? In the 1950s, he's accused.

And he brasses it out.

CHARLOTTE PHILBY: At that stage, there aren't many options open.

He'd first become embroiled in this world aged 19 or 20.

He was used to it.

He knew no other way of being,

other than living as two separate characters

and having to do so with a great sense of conviction.

CORERA: Kim Philby, I think, had a unique hardness of his character,

an ability to deceive and maintain deception,

in the way he was able to betray his colleagues.

"Is he the third man?", they ask.

There've been these questions in Parliament about him.

And he just brazenly lies and denies it all.

INTERVIEWER: The Foreign Secretary has said that, in the past,

you had communist associations.

Is that why you were asked to resign?

I was asked to resign because of an imprudent association.

That was your association with Burgess. Correct.

What about these alleged communist associations?

Can you say anything about that?

The last time I spoke to a communist,

knowing him to be a communist, was some time in 1934.

The man is clearly lying. He's got a smirk on his face,

you know, when he's denying it. I don't find it very convincing.

Other members of MI6 just don't believe he could possibly be a spy.

They almost don't want to confront the possibility

that their friend, Kim Philby,

a person many looked up to as the future of MI6,

could possibly be a traitor. They just do not want to believe it.

Of the Cambridge Five, Philby is the star.

Perhaps Philby is the greatest spy of the 20th century.

Anna Chapman is the glamorous daughter

of a high-ranking intelligence officer

who was sent to New York to glean secrets

which she would then send back to Moscow.

It sounds like something out of Ian Fleming

because it basically was.

The KGB have had two types of spies.

They've had the legal ones that operate out of embassies,

and then they've had what are known as the illegal spies.

CORERA: An illegal doesn't have diplomatic immunity.

They are pretending, for instance, to be a businessman or a book seller

or something like that.

And that means if they're arrested, they can go to jail.

You pass them in the street, they look like your fellow citizens,

but they're not.

Anna Chapman comes over as a teenager to the UK

and she falls in love and marries a young British man

and gets a British passport.

It's not clear exactly when she becomes an active agent.

And at one point, she goes back to Russia and she comes back to the UK,

and starts expressing an interest in going to America.

And it does seem suspicious, as if it might have been an order

from Russian intelligence.

Now I know a lot of people introduce me to someone else,

and those introduce me to someone else.

So now I know where to go if I have something to solve.

She has the ability of someone

to engage with influencers in Washington,

and to gain the ear of individuals.

So there's often deception in different elements of spying.

It's not necessarily about trying to steal secrets

from people in government in the way that, for instance, Kim Philby did.

It's about spotting people who are influential,

who are on their way up, who know the gossip,

who know the inside track.

It's about reporting back on those people to Moscow.

We do know that the US had sources within Russian intelligence

who were able to tip off the United States

about the presence of ten illegals living in the United States.

So while she was doing her spying, they were watching her,

they were surveilling her.

The FBI and CIA decide to move towards arresting

those Russian spies in America.

They round up the illegals, including Anna Chapman.

And so she was busted

and repatriated back to Russia in a spy swap.

IN RUSSIAN:

I did what I did not to make money,

but to help prevent the defeat of a new system.

It came as an enormous surprise

to the then-ministers in the government.

They'd no idea that this individual had been identified

as being a Soviet spy.

I thought that perhaps some of what I had access to

might be useful in helping Russia

to keep abreast of Britain, America, and Germany.

And it's a remarkable moment because people are asking questions.

Well, firstly, "Why did she do it?"

Secondly, "Why was she not caught?"

Her mother had been recruited into Soviet intelligence,

had been active in the 1920s as a spy.

So in a way, Melita Norwood had been radicalised

from a very, very early age.

She was recruited in 1934,

and, of course, then she was only 22 years of age.

Her position is working as a secretary

for a company engaged on Tube Alloys, on nuclear research.

This is a top-secret project. It's the atomic bomb.

Not even... You know, the Cabinet doesn't know about it.

She's sitting in the back room taking notes,

nobody really suspected her.

Her lowly position means that she is often underestimated

in the information she could collect.

Actually, she's in a key position as the secretary

who can see all the information and provide it to the Russians.

NEWSREEL: Melita Norwood, now 87 years old, great grandmother.

Yet it is claimed she was the most important British female agent

ever recruited by the KGB.

In 1999, I telephone her and she said,

"Oh! I've been a very, very naughty girl.

"I'm afraid I've got the world's press camped in my front garden

"wanting to interview me about my past."

Which seems to have been a bit colourful.

When it emerged that she had been a spy,

there was this question about what to do about it.

And I think in MI5, they clearly thought,

"Well, she's old, she's not active any more,

"there's no risk," so nothing is done.

The Soviet Union, the KGB, were masters of using illegals.

They really hold up these spies as, if you like, the pinnacle of spying.

Those people who are able and willing to go under deep cover

into the west or other countries, potentially for decades.

It is the undercover spy, that sleeper,

who the Soviets were very, very good at putting in place,

who were the most successful.

And I wouldn't be surprised if they were still capable of doing it.

And still do so.

HARRY FERGUSON: I would say the most dangerous time is when your agent

is trying to communicate their intelligence.

They may be photographing a document or taking a sample.

But the point where they have to communicate that intelligence to you

as the officer, so that you can get it back, that's tricky

because you might be being watched.

If something goes wrong and that person is discovered,

it is the agent, really, who's gonna face the consequences.

What they often need to rely on is their own wit and imagination

in order to deal with the threats that they face.

If you're in a very hostile environment and your cover is blown,

you get out as quickly as possible

and you will have an exfiltration plan,

which has been worked out before the operation.

It might be as simple as jump in your car, drive to the border,

just head straight over it.

INGRAM: You'll have rehearsed it on tabletops and all the rest of it,

just to go through all of the different stages.

It happens with all of the high-grade agents that are there

that may be in a position where you need to extract them.

AIMEN: I received a text message form an Al-Qaeda associate of mine.

He was telling me, you know, "Go to the Times Magazine website."

It says, "Human intelligence source uncover a plot

"to attack a New York subway using chemical weapons."

And I realised, basically, that I was the source.

Aimen was, luckily, out of Afghanistan,

and out of Al-Qaeda's immediate control.

He was named in an article that got published.

It contained leaked intelligence from the CIA

and stupidly, they used my first real name.

There were clear suspicions in Al-Qaeda,

so they knew there was a mole there somewhere.

A group like Al-Qaeda is aware

of the danger of infiltrators in its ranks.

And if Aimen Dean had been discovered,

he'd have almost certainly been killed.

There will have been contingency plans put in place

that he will have known very little about,

but they'll have all been worked out beforehand

as to how to potentially get him out of there.

I immediately called my handlers back in London,

even though it was Sunday, and I was told basically that,

"Sorry to tell you, but your spying days are over."

When you're sharing intelligence, the intelligence comes out,

you've got no indication as to who the individual is,

or the individuals are that's supplying that intelligence.

National agencies, when they get jealous,

will task some of their team to find out who it is.

And I think that's how Aimen's name then got into discussion.

And it's very dangerous, and that's almost certainly what happened here.

Given the fact that I caused the death of at least one or two

of their senior leaders in Saudi Arabia, I would say yes,

they are angry, enough to try to kill me twice.

Betraying them is an act of honour, not an act of dishonour.

CORERA: The evidence is strong enough that MI6

can no longer really resist

the thing that they've been trying to deny for so long,

that this man who'd worked at the very heart of MI6

is actually a spy.

And one of Philby's friends, Nicholas Elliott,

is sent out to Beirut, where Philby is living, to confront him.

WEST: Nicholas Elliott said that when he knocked on the door,

Philby had said the equivalent of, "What took you so long?"

He was offered an immunity from prosecution

by the Attorney General, which he accepted.

And he then made a confession.

It does look like Philby

still manages to pull the wool over his friend's eyes

and convinces him that he's willing to talk

and that perhaps there's some kind of deal to be done.

But a few days after having handed that confession,

he simply disappeared.

QUESTIONER: Do you think MI6 wanted Philby to escape from Beirut?

No, I don't think so,

because they wanted him to collaborate with them again.

And therefore, we decided to take him away from Beirut by boat.

He collected his things, he didn't say goodbye to his wife.

CHARLOTTE: I've spent a lot of time trying to imagine

how he must have felt boarding that freight liner in Beirut

to Moscow, knowing that he could never come back.

Knowing that his children and his friends and everyone

would soon know the truth.

He was reserving a whole part of himself and his life

and keeping that secret from his wife and his children.

And the mental impact that must have, I just think is huge.

Can you imagine waking up every morning and...

and just having that moment of worrying

that you might have said something

that would give you away as a traitor?

Deception has always been at the heart of spying

because spies work by hiding who they really are.

Is it intelligence? Is it covert action?

It's a little bit of all those things,

which is why deception is such a challenging area of spy artistry.

If you think of the stakes, you'll tighten up.

You've got to act naturally, while at the same time,

doing one of the most unnatural things in the world.

The profession exists to intrude covertly into other people's lives,

to collect information about them,

to understand the risk that that person might pose.

This is a crucial part of the job which has remained unchanged.

Assassination is something that any service could do,

but doesn't necessarily have to do.

There was enough Novichok there

to kill tens, if not hundreds of thousands of people.

Putin and Litvinenko themselves are personal enemies.

The order is kill Litvinenko.

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