brought to you by Aspire Mungfront on ITVX, a six-part drama of friendship and betrayal,

starring Damien Lewis and Guy Pierce. The coldest war is within.

Aspire Mungfront, stream free on ITVX.

Disclaimer. This episode features strong language throughout.

Incoming transmission. Welcome. Welcome. Welcome. Welcome to True Spies.

Week by week, mission by mission. You'll hear the true stories behind the world's greatest espionage operations.

You'll meet the people who navigate this secret world.

What do they know? What are their skills? And what would you do in their position?

This is True Spies. We were going to negotiate to buy the largest parcel of heroin that would ever have been seized inside the UK.

They told us that they would accept payment in weapons instead of money.

Episode 50. Operation Zulu Cricket.

It's 1993. You're a top undercover operative. And you've just been told about the biggest job of your life.

After painstaking work, you set up the trade.

Out comes to the room, carrying this large and heavy hold-all. I take it. And inside, there are 30, half kilo packages of heroin.

The violent gangster selling the trucks is on edge.

He was like a cat on a hot tin roof. He just couldn't wish the time away quick enough.

I was a lot more relaxed through all of this than I was.

That's because this week's True Spie was one of Britain's best. A work hard play hard detective.

He was a founding member of Scotland Yards undercover unit. A master of disguise.

He infiltrated criminal gangs and scammed the scammers out of millions of pounds worth of drugs and counterfeit money.

By his early 30s, he'd earned some of policeings top honors.

But then, a long came a job that would change everything. Coat name, Operation Zulu Cricket.

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