Original subtitles

'The Millennium Dome, icon of the year 2000...'

CHEERING AND APPLAUSE

'..home to a celebration of the new century.

'And on display at its heart,

'the £350 million Millennium Diamonds.'

It's beautiful. Really amazing.

In November 2000,

this seven-tonne earthmover made headlines around the world

when it was involved in the biggest diamond heist

in British criminal history.

CRASH

I heard the crash,

turned around, realised, oh, my God, it's coming in.

'A criminal gang had one target -

'the Mona Lisa of diamonds.

'But could the police stop them?'

The gang could easily grab a member of the public,

use them as a human shield.

The Home Secretary would have known about it.

'It's a story from the end of an era in British crime...'

'It's the biggest robbery in the world.'

It's old-school robbery, it's kind of out of a movie.

'..told by the police, many speaking publicly for the first time.'

SIREN BLARES I was going to have to take action,

shooting the driver.

'With evidence never seen before,

'I'll reveal a nine-month cat-and-mouse game...'

I was over there, hiding in plain sight.

'..between cops and criminals...'

We heard the words, "Attack, attack, attack."

POLICE RADIO CHATTER

'..played out both on water...'

I'm in the barrel of the boat,

shouting, "Armed police, show us your hands."

'..and on land.'

We had stun grenades. Explosions, flashes, noise, smoke.

It was chaos inside there.

'This is the untold story of one of the most audacious gem raids

'the world has ever seen.'

CLOCK CHIMES

'Two decades ago...'

'A celebration, the most spectacular ever seen.'

'..this space-age building, the Millennium Dome,

'opened in Greenwich with a spectacular party.'

# Why does it feel so good? #

I actually came here for New Year's Eve 1999,

for the grand opening.

The Queen was here, and the then-Prime Minister.

I, erm... I think I had a good time.

FIREWORKS CRACKLE

# Why does it feel so good? #

'20 years on, I'm back

'to investigate a gangland robbery which defined the millennium age.

'Built to celebrate the year 2000 with a great public exhibition,

'during the 12 months it was open,

'the Dome drew six and a half million visitors.

'When it closed, the space was cleared

'and the interior transformed.

'Today, there's a cinema and shopping complex around the edge,

'whilst the middle's become a massive indoor concert arena.

'20 years ago, acrobats flew high above the crowds.'

'Welcome to your capsule, interplanetary travellers.'

'Around them, the space was divided into 14 themed zones.'

GROANING

'Inside the Money Zone,

'visitors were greeted by £1 million stuck to the walls and floor.

'But what they really came to see... was this...'

ETHEREAL MUSIC PLAYS

'..the Millennium Jewels,

'a collection including the Millennium Star -

'the second largest flawless white diamond in the world.

'Discovered in former Zaire in the early '90s,

'the De Beers Millennium Star,

'together with the smaller jewels, were valued at £350 million.'

SHE GASPS, LAUGHTER

Well... you can imagine how I feel. It's beautiful.

CAMERA SHUTTERS CLICK 'In 2000,

'the jewels were on display in a vault at the Dome's Money Zone.

'Today, I'm back inside the Dome

'in search of the place where the exhibit was built.'

So, the Millennium Star was in this area,

and it was positioned very close

to one of the iconic, giant yellow tent pegs.

It's not yellow any more because it's been insulated

because of fire regs.

But that means I'm standing on the exact spot

where they built the Money Zone.

'And it was to this spot, 20 years ago,

'that a gang of robbers headed.

'Their target - the Millennium Jewels.'

'The heist begins in the morning rush hour.

'Surveillance footage picks up a seven-tonne digger

'closing in on the Dome.'

So, the JCB races up this ramp with four of the gang members in the cab.

When it gets to this gate, it smashes through it.

CRASH

Now, it's really on the move, and it's headed for that delivery door.

'Unstoppable, it careers through the steel door.'

CRASH

'Visitors inside are unaware of what's happening.

'But someone else is.

'Seconds before impact,

'a Metropolitan Police officer is just yards from the shutter.

'Carol, from the Met's elite surveillance arm, SO11,

'is now part of one of the most dangerous ambushes

'in Flying Squad history.

'This is the first time she has ever spoken about the raid.'

So, how soon after you took a peek through the shutter

did a JCB come smashing through it?

Erm, probably about five-ten seconds afterwards.

Really? Yeah.

I mean, if we'd have been stood there,

we wouldn't have had a chance.

We heard the crash, turned around,

and realised, oh, my God, it's coming in.

It was this huge JCB with a bucket on the front,

and I just remember the bucket bouncing up and down.

Orange flashing lights. It was going fast, it wasn't stopping.

It's coming your direction. It's coming straight for us.

So we turned and ran.

You carried a weapon, though, yeah? Yes, we were armed.

But my weapon was in a bum bag...

ROSS LAUGHS ..which was around my waist.

Not that easy to draw as a JCB is coming at you at 20mph!

That didn't enter my head. I was fleeing, we were both running.

'The JCB has gone in through, beeline.'

Couple of them jumped out, threw smoke grenades on the ground.

Then, absolute pandemonium.

It was frightening. We ran cos it wasn't stopping for anybody.

'What Carol saw two decades ago

'was the beginning of a spectacular robbery.'

CRASH

'Dogs' by Pink Floyd.

Carol's not only a brave woman, she's incredibly lucky to be alive.

'But it was no accident she was there at the Dome's Money Zone.

'I want to discover the untold story behind Operation Magician,

'led by one of the world's most famous police departments,

'the Flying Squad.'

When I was a kid, my father served in the Flying Squad.

And though he never spoke much about his job,

I do know that their main aim was to catch armed robbers

in the act of committing a crime,

because they stood a better chance of securing a conviction.

But that takes a heck of a lot of effort and a lot of resources.

And that was never more true

than in the case of the Millennium Dome diamond heist.

'The story of the heist begins nine months earlier...

'..not at the Dome, but here in south-west London.'

'Close to Nine Elms Lane,

'in the shadow of Battersea Power Station,

'Flying Squad Detective Steve Deboer

'races to the scene of a violent robbery.'

SIRENS BLARE

'This is the first time he's spoken about the attack.'

Hello, Ross. Steve, how are you?

'A gang had cornered an armoured van carrying 10 million in cash.'

The van came from the left, there, drove up,

and, from this direction, a stolen BMW intercepted it,

completely blocking it. So...

£10 million worth of cash is in that vehicle.

What happens next? The robbers jump out of the BMW.

They're wearing black balaclavas, black military-style uniforms.

And where they armed? They were, yes.

'Holding back passers-by at gunpoint,

'the gang have also triggered gridlock,

'blocking Nine Elms Lane with two lorries.

'But a third vehicle, disguised with Christmas trees,

'is their secret weapon.'

Hidden amongst those Christmas trees was very sharp spike, solid steel.

God! ROSS LAUGHS

Wow.

They've turned a vehicle into a hammer

with a spike in the end of it.

That's concreted in?

Yeah, that's solid, and there's concrete in the lorry.

So their objective was to ram that spike into the rear doors?

That's exactly right, yes.

'But there's a problem.

'Having parked the lorry earlier, the keys have now gone missing.'

So, when they go to ram the back of the security vehicle,

they get in the cab, no keys.

The robber goes to the van,

he's looking on the top of the wheel.

Goodness knows how long has elapsed.

The leader's got a stopwatch, he calls time.

They set off incendiary devices in the vehicles,

destroying all the evidence.

And then they jog down here, past Battersea Power Station,

to a high-power boat,

and escape up the Thames towards Chelsea.

How well-planned was this, Steve?

This was so distinctly different, it rang alarm bells.

They'd thought about just about everything.

The one thing they didn't take into account

was somebody nicking their keys.

Now, the gang don't get any cash, but they don't get caught, either.

And with the vehicles torched,

the Flying Squad have no clues as to who this gang actually is.

No forensics, no nothing.

'Today, thanks to advanced CCTV, modern forensic science,

'and sophisticated phone and vehicle tracking,

'holding up a cash truck or post office is high-risk.

'But before all this,

'gangs were often one step ahead of the Flying Squad.

'At its peak in the early '90s,

'there was around one raid in London every day.

'After the Nine Elms attack,

'the Flying Squad fully expect the gang to try again.'

And five months later, they do.

Another ambush.

The gang are wearing combats, boots, balaclavas and helmets.

'The attack, at Aylesford in Kent, is a carbon copy of the first.

'But it becomes more violent.

'A security truck is carrying nine million in cash.

'A steel spike mounted on the back of the lorry

'rams the cash truck twice.

'The spike is identical to the one used on the Nine Elms job.'

The police arrive, but the gang force them back, firing a gunshot.

'Leaving empty-handed, the gang head for a nearby river

'and their escape on a speedboat.'

But crucially, though, this time, the Flying Squad have a lead.

'Police have seen one of the lorries used at Aylesford

'at a farmhouse 15 miles away.'

Just over there is the farmhouse.

And coincidentally, for entirely different reasons,

Kent Police already had it under surveillance.

'Occupant Lee Wenham, seen here driving,

'is suspected of criminal activity

'which could involve the lorry used in the second raid.

'Within days, there are more sightings.

'First, a stolen digger arrives at the farm.

'And then... this.

'A speedboat.'

CAMERA SHUTTERS CLICK

The police are making progress.

A speedboat was used at Nine Elms and at Aylesford,

but it doesn't actually prove anything.

The Flying Squad are going to need more, a lot more.

And soon... they get it.

'Police film three new faces arriving at the farm.

'Joining Lee Wenham a Terry Millman,

'a known south London gangster

'who's done 14 years for armed robbery.

'Ray Betson has convictions for fraud and theft.

'And William Cockram has done time for ram-raiding

'and handling stolen goods.

'The men definitely have form.

'So, could they really be responsible?

'I'm back in London to find out what Steve Deboer thinks.'

I think, although there's no direct evidence to link them

to any previous robberies,

Betson and Cockram are really close,

they're really tight.

The one that's the interesting one is Millman.

He has got a long record, including armed robberies.

If you look at their skill set together,

they've got everything it takes to carry off a significant robbery.

'Whether these men did the first two raids or not,

'could they be plotting a new job?'

Well, they haven't got any money yet,

so I'm convinced that they're planning a robbery.

And to get them convicted and put away,

we need to really concentrate

on getting the best evidence that we can.

And there's only really one way to do that.

That's catch them in the act.

'With the gang now identified, surveillance in Kent is stepped up.

'Seven weeks later, police tail Lee Wenham's car from the farm...

'..to London.'

If the gang were responsible for the first two raids,

then the police believe they'll strike again.

Probably in London, and possibly close to the Thames.

But where and when?

Frankly, the Flying Squad don't have a clue.

Well, that is until Lee Wenham gives them a pretty big one.

He goes to the building that everyone's talking about...

the Millennium Dome.

Since it opened in January 2000,

millions have visited the Millennium Experience.

It's now August,

and police tailing suspected armed robber, Lee Wenham,

are secretly filming him at the Dome.

With a woman and child in tow,

the first thing he does is inspect a security gate.

Inside, police disguised as tourists

film him visiting the Money Zone three times.

Wenham appears fascinated by a gem collection,

including the Millennium Star,

the second-largest perfect white diamond in the world.

That's when the penny drops and the police realise that

Wenham and his pals must be planning to steal the Millennium Star.

If the gang pull it off,

it would be the equivalent of 12 Great Train Robberies...

seven Brinks-Mat bullion jobs...

and 38 Hatton Garden safe deposit heists.

It would quite simply be

the biggest and most audacious robbery in British history.

That is, of course, unless the Flying Squad could stop them.

Both the Nine Elms and Aylesford raids

involved attacks on security trucks when they were on the move.

Now police learned that in a week's time,

the diamonds are due to be moved.

The seven-mile journey from the Dome to De Beers' head office

is the first leg of a trip to Japan,

where the gems will appear in a temporary exhibition.

As part of this journey, the security truck

has to go under the Thames, through the Blackwall Tunnel.

That's not a bad place for an ambush - well, at least,

that's what the Flying Squad think.

They also believe the gang may possibly have an insider.

That's when they start planning their own ambush.

On the morning of 1 September, eight Flying Squad cars are in position,

aided by motorcycle, helicopter and river support.

It's a huge operation.

The police are even watching the homes of De Beers employees

in case their families are kidnapped.

Just after 9:30 AM...

HELICOPTER BUZZING ..the operation begins.

As the cash truck enters the tunnel,

unmarked Flying Squad gunships melt into the traffic around it.

But then, for two crucial minutes,

the mobile service drops out.

But nothing happens.

Not in the tunnel and not anywhere else en route to central London.

It's cost a fortune and it's all for nothing.

For the police, this is a major setback.

Caught on the back foot,

the Flying Squad can only conclude one thing.

When the diamonds return from Japan,

the gang must be planning to steal them from inside the Dome...

..but that should be impossible.

The Dome exterior is protected by a high perimeter fence

and regular security patrols.

But getting in is the easy bit.

The diamonds are displayed in a vault

built with ram-proof concrete walls.

Visitors enter the vault through a high-security door.

DOOR SLAMS SHUT

Inside, the display vault cabinets, one housing the smaller diamonds,

the other, the Millennium Star, are fully alarmed.

The glass is designed to withstand hammer attack

for a minimum of 30 minutes,

while CCTV in the vault is monitored both by Dome staff

and DeBeers own security,

watching at head office seven miles away.

With the jewels now due back from Japan,

police believe the gang will strike during the day

when the vault is open.

Gang members Betson and Cockram are secretly filmed casing the joint.

But confronting them in the vault, surrounded by visitors,

would be a high-risk operation.

So, to work out a strategy,

detectives call in the Met's specialist firearms unit,

SO19.

Steve, one of SO19's most experienced officers,

is asked to help with the arrest plan.

You're in an open area.

How important is the element of surprise?

Well, surprise is everything on an ambush.

If you're seen coming from a distance away,

your quarry are going to bomb burst.

They can break away, they can take hostages...

they can open fire,

so the big problem we had, we needed somewhere

where we could conceal ourselves until the robbery took place.

You wanted to catch them red-handed. Catch them red-handed, exactly that.

But at the time, this was an open space

and how do you get an element of surprise in an open space?

And it wasn't until we went back to the base

and we looked at the plans for the Dome

that we realised down in the basement, there was a tunnel.

Below the exhibition floor,

SO19 discover a 100m-long service tunnel.

Several metres wide, it runs in a straight line

from the outside edge of the Dome right into its centre.

Protected by fire doors,

a staircase rises up to the exhibition floor at ground level.

Crucially, the exit point is only around 50m from the Money Zone,

which makes the basement the perfect place

from which to launch a surprise attack.

You've worked out you've got somewhere that you can hide,

but can you really hide here?

Well, that was the issue.

We needed somewhere where we could stay out of sight

for up to 10 hours,

but could we stay here unseen? People are using it.

It wasn't fit for purpose, obviously.

Wary of an inside job,

only a handful of trusted Dome staff can know SO19 are here.

So, to stay out of sight,

they construct a fake, windowless storeroom at one end of the tunnel.

You walk through the door. That's right, yeah.

And how deep was it?

Well, initially, it came about two thirds down here to about here.

Yeah. And then later on, as things developed

and we needed more people to cover more contingencies,

they added another ten feet onto it.

So you've now got your hide.

Yep. You're equipped, what else do you need?

Well, I suppose the icing on the cake

is knowing exactly when the job is going to go down.

And that is always the million-dollar question.

Desperate to know the date of the jewel heist,

police step up intelligence operations.

There's a breakthrough as new gang member Aldo Ciarrocchi is filmed.

Then, in early September, the speedboat leaves the gang's hideout.

'Spies' by Coldplay

On the 12th, it arrives at Whitstable in Kent.

# The spies hide out in every corner

# But you can't touch them, no

# Cos they're all spies... #

GIRL SCREAMS

Jools Lloyd and his undercover team

have been following the gang for several months.

This is the first time he's spoken about filming them at Whitstable.

Where'd they launch the boat?

They launched the boat from this ramp here.

The one we're stood on? The one we're on, yeah.

And I was over there, where those cars are parked now.

They... They took it out.

I think they were out for about 20 minutes or so in all.

And there, you've got Bill Cockram and Ray Betson.

Yeah. Both in the speedboat.

That's here, isn't it? That's right, yeah.

They don't know they're being photographed.

They don't know they're being photographed,

let alone followed, no.

And they're taking precautions not get noticed, aren't they?

They're taking precautions.

They have got baseball caps on, they're wearing sunglasses,

and, if you look closely, you'll see that

Cockram's wearing some petrol station forecourt gloves,

which is a great but crude method

of just not putting your fingerprints all over the boat.

And it's not something you'd normally do

if you were just going out for the day joyriding. No, it's not.

So, that goes to show these are career criminals, yeah?

These are career criminals. They're doing good preparation for the job,

probably to test... For the boatman to test the driving

and the handling of the boat,

but also just to test that the boat was match-fit.

So, you've got no hard evidence to connect these guys

to the two other robberies, but what's your gut feeling?

We've got two previous robberies where...

A boat's been used. ..a boat's been used.

And it's... You know, it's unique.

We were on the right people, we knew that.

And then you kind of start getting excited a bit,

and, on a personal level, I knew that they'd go for another job,

and we came away quite convinced that the job was imminent.

Soon, there's more evidence that the day of the heist is close.

The gang move the stolen digger from the farm in Kent

to an old coal yard close to the Dome.

'But it seems they're not happy with the getaway boat.

'Surveillance footage shows Terry Millman buying a new one.

'He pays £3,700 in cash.'

And it was quite an upgrade.

The new speedboat has a racing propeller,

making it capable of doing 50mph,

which means it was probably fast enough

to outrun most things on the water.

Millman also displays a sense of humour.

When he pays for the boat, he signs his name as Mr T Diamond.

Police are now in no doubt

that the gang will try to escape on water.

Clive Rew, from the Met's firearms unit,

is asked to plan a potential river arrest.

He's never spoken before about his role in Operation Magician.

What was the first thing that you planned to do?

The tactical plan is to be as covert as you can until the last moment,

and then speed, aggression, surprise,

using two police boats, minimum,

so that we overwhelm them as fast as possible

with superior firepower and superior numbers.

And there is a real risk of a firefight on the Thames.

A very realistic prospect of that.

These were desperate criminals,

facing a long stretch in prison if they got caught.

So, you know, as you can see, we're moving up and down now.

You have a firefight on the Thames,

that means the rounds could go in any direction.

Yeah, they have no rules, so they can fire willy-nilly at us.

We can't do the same to them. This is not a military operation.

And was there a fear that they could take hostages?

That was one of my fears.

If the gang were so desperate to get away,

they could easily grab a member of the public,

take them as a hostage, use them as a human shield.

How close would you need to be to be able to engage them safely?

On a moving platform with a Heckler & Koch MP5,

we really need to be 50m and less to successfully engage

with the upper torso of an armed robber.

The ambush is fraught with danger.

But now, the police are ready.

And they've got the final piece of the jigsaw.

Police have filmed the gang on one last recce of the Dome.

Outside, as they scrutinise tide levels,

police realise that only high water

will give the gang the escape options they need.

The next big high tides are due...

..so the Flying Squad mobilise...

HELICOPTER BLADES WHIRR ..and set their trap.

The police have assembled a small army of officers,

from the Flying Squad, SO19, SO11 and other units.

They're in helicopters, they're on boats, they're in cars,

they're motorcycles and they're on foot.

And there are cameras everywhere.

INDISTINCT RADIO CHATTER

They've even placed a camera

in Britain's tallest building at the time,

the Canary Wharf tower.

Undoubtedly, this is the biggest and most expensive operation

ever mounted by the Flying Squad.

But... will it work?

Leading the police ambush

are members of the Met's armed response unit.

Disguised as cleaners, at 3am,

they're smuggled into the Dome's basement tunnel

and into their secret hide.

Steve is one of them.

Where were you, Steve? Well, I was over here, Ross.

I was, erm... the second person to be going out.

I had one other guy who had a big ballistic shield,

he was gonna lead the way, and I was gonna be with an MP5 carbine,

and we would be first out.

Behind us, there was the rest of the team,

and, right at the very rear, the team medic.

We had to keep quiet in here.

Sleep, read a book at torchlight. Mm.

Go through some of the equipment that you would have had on you.

Each officer had their own body armour,

ballistic plates in there,

er, ballistic helmets, a respirator,

a belt rig with your pistol, which was the Glock,

and the MP5, and four stun grenades each.

So, ultimately, you are the arrest team.

You're the tip of the spear.

I mean, it's quite a responsibility, because, effectively,

everyone is relying on you,

and it's all coming down to us, at the end of the day,

being the ones who are gonna go up there and arrest them.

Catch 'em at it.

And if you fail in that, it's down to you, isn't it?

Early morning...

..and the digger is on the move.

We were all really excited.

So, as far as we were concerned,

everybody was concerned, the job was on.

And we also got the word of the gang's speedboats

in the sea near the Dome.

Everything was in place, and it was all happening.

But there was still gaps in our intelligence picture.

We knew that the JCB was involved in some way,

but we didn't know exactly what the involvement was gonna be.

We needed them to actually attack

the armoured glass inside the exhibit,

otherwise, they could probably get off at court.

But there's one nightmare scenario:

a shootout inside the Dome,

with families and school children everywhere.

People in Government were aware of what was going on.

The Home Secretary will have known about it.

If it goes correctly, everybody's congratulating people on the plan,

but should it not go to plan and somebody get hurt,

somebody has to justify those tactics.

As the digger arrives and smashes through a perimeter gate...

CRASHING

..the reputation of the Metropolitan Police

and every one of its officers hangs in the balance.

'The Dome had shutters, and they were down, they were closed,

'so we walked towards them and had a peek out.'

Couldn't see anything, so we decided to walk back

towards the Money Zone.

And when we were about 15 feet away...

CRASHING

..it came crashing through directly behind us.

We were like, "Where is it?" Then... communications coming over the air.

CRASHING, INDISTINCT RADIO CHATTER

It's come through the side of the Dome.

We just ran.

And it came behind us and followed us around to the left.

And then it passed, and then it did a U-turn.

It came to a halt outside the jewel exhibit.

In the basement, Steve and arrest team break cover

and head to a forward attack position on the stairs.

We got to the top of the stairs. HEAVY BREATHING

Beyond that door was the public.

That was the last point before we're committed.

MUFFLED BANG

After throwing a smoke bomb, one of the gang members

stands outside the vault - another goes inside.

There was a feeling of adrenaline. It was exciting.

If they wanted those jewels,

they were gonna have to smash their way through to get them.

It's high tide on the river as the gang's boat arrives.

I got a call, and, at that point,

my RIB and the fast speedboat that the police had hired

made its way to the Millennium Pier.

The run time for that was less than three minutes.

TOOL WHIRRING

Inside the vault, the gang attack the display cabinets.

GLASS SHATTERING

It's diamonds, it's old-school robbery.

It's kind of out of a movie, really.

We waited... and waited.

HEAVY BREATHING

Time slows down. It's quite weird.

And then... it came over the radio, those words we'd been waiting for.

"Attack, attack, attack."

At London's Millennium Dome,

a criminal gang are in the middle of a £350 million diamond heist.

But the police are waiting.

When we heard the words, "Attack, attack, attack..."

..we spilled out onto the concourse.

Get out of the way!

All of a sudden, out of every orifice,

the SO19 guys just came out from all directions.

'The attack's gone in.'

Biggest thing for me was that JCB.

Get out of the way!

Should he start revving the engine, or if I heard gunshots,

I was gonna have to take action,

which may involve shooting at the driver.

Outside, the getaway boat is on the move.

The man at the controls has radio contact with the gang.

The plan is for him to make his way over to the Dome's private wharf

as the gang make their escape.

TOOL WHIRRS

The rest of the gang were in the vault.

Adrenaline's going.

Everything happens in... in seconds.

GLASS SHATTERING Nothing is too overwhelming.

With members of the public about,

we didn't want any runners with guns,

because he's fleeing 20 years.

We took on the guys throwing these smoke bombs and stun grenades,

and he was placed on the floor.

I then moved round to the side of the JCB.

The driver put his hands up

off the wheel, which was something that...

that helped me and him.

The driver is Ray Betson.

As he started to climb out, he said to me,

"It's all right, mate, this is nothing to do with me, I work here."

I knew, obviously, that he didn't. CHUCKLES

GLASS SHATTERING

With overwhelming force, police swarm into the vault.

We made the entry using stun grenades.

They generate smoke.

Explosions, flashes, noise.

A confined space, it was chaos inside.

They were on them in seconds. There was lots of shouting.

They're surrounded.

Frightening.

They arrest two men.

One is William Cockram, the other, a new face,

later identified as Robert Adams.

HELICOPTER BLADES WHIRR

On the river... 'I see a boat with...'

..firearms officer Clive Rew is leading the getaway boat ambush.

Our single goal was to get to the getaway boat...

'Boat's going on in there.'

..and ensure that didn't make off.

'Follow him.'

If the driver of the boat engaged, we would have no alternative

but to stop that threat using the central torso hit.

The impact is likely to stop that suspect fairly instantly.

'Standby.'

The speedboat is unaware until the very last few seconds,

when we're on top of him.

I'm in the bow of the boat shouting, "Armed police, show us your hands,"

because the danger comes from someone's hands.

He put his hands up and presented no threat.

'Got him.'

Then I formally arrested him for conspiracy to rob.

He was just silent.

Looking very, very, very sheepish,

as though his world had come to an end.

Armed police next arrest Terry Millman

on the north side of the river, posing as a road engineer.

Simultaneously, Lee Wenham is picked up at the farm in Kent.

The arrests were over in minutes,

but it turns out the gang weren't armed.

Unless you count this powerful nail gun,

which was used to weaken the glass

before they hit it with a sledgehammer.

NAIL GUN WHIRRS

The cabinets were designed to be impregnable,

but the Hilti nail gun had caused the glass to fail

in less than 30 seconds.

The Hilti had a bad reputation for doing jewellery robberies.

They wouldn't have sawn-off shotguns, they'd have Hilti guns.

Just blew my mind that, all this security,

and they had defeated them

with an in industrial nail gun and a sledgehammer.

HELICOPTER BLADES WHIRRING, DISTANT SIRENS

All of the robbers had been secured. No-one's been hurt.

It's a good feeling. The headlines were great.

I don't think we quite realised

how much media attention there would be on it.

'A number of men, mostly middle-aged...'

'JCB digger has been left here by police...'

'Had they succeeded, it would have ranked

'as the biggest robbery in history.'

It was a good day for... for the police that day.

The trial at the Old Bailey lasted three months.

Found guilty of conspiracy charges,

six gang members were given sentences

of between five and 15 years.

The seventh, Terry Millman, died of cancer before the trial.

The amount of evidence was overwhelming.

We'd caught them red-handed in the Dome trying to take the diamonds,

so there was no way they weren't gonna get convicted.

Lee Wenham got four years for the Dome

and a further nine years for the Aylesford attack.

There was never evidence to charge any of the others

for either Aylesford or Nine Elms.

These guys were cunning.

They had bravado, and they were certainly persistent.

It took four months to plan.

They used a JCB like a tank to smash their way in.

They would have been in and out in minutes,

and they would have made a James Bond-style getaway in a speedboat.

They're desperate men, to risk 20 years.

OK, they didn't hurt anybody, but if we hadn't have been there,

Mum and her three-year-old child in a buggy

could have been the other side of that tent

as it came crashing through.

But did the police get everyone involved?

At the trial, the gang said a Dome insider had helped them,

but the claim was dismissed.

There was also speculation about a mysterious Mr Big.

So, did a Mr Big really exist, and, if he did,

was he a powerful South London gangster

or a member of an international organised crime group?

Well, the police say no.

They maintain the gang organised the entire thing.

And the truth?

Well, the truth is, we'll never really know.

Not for sure.

For a brief moment, the gang were famous,

but, two decades on, it's hard to remember their names.

'I do remember this, though.

'Today, the digger used in the robbery attempt

'is getting a rare public outing.

'The four men who squeezed inside the cab

'on the way to the Dome, together with their accomplices,

'were, in many ways, the last of an old breed.'

It was a crime of its time,

and we'll probably never see its like again.

These days, it's far easier to rob with a laptop.

There is one final twist to the story.

The gang hoped to become rich beyond their wildest dreams,

but to make sure this didn't happen,

before the raid itself, the real diamonds...

..were swapped for fakes.

In fact, the JCB was probably worth more than the fake diamonds.

If I'm gonna be honest here, I've a sneaky respect for them

that they had the balls to get up out of their chair and do it.

BANGING, GLASS SHATTERING

But they're breaking the law. You can't have people doing that.

Subtitles by ITV SignPost