M.I.5 and M.I.6, the intelligence agencies that protect the country from threats at home

and abroad have always been cloaked in mystery.

The government didn't even confirm that M.I.6, or the Secret Intelligence Service, existed

until 1994, so it's extremely rare outside of fiction to get a glimpse of how they operate

until you hear a story like this.

There's this sort of filmic caricature of what a spy looks and sounds like.

There may not be a verse to Martini's and sitting in airport lounges wearing aviators

and then there's the reality of it.

That reality is murkier.

Today's story, which involves scenes of extreme violence that might not be suitable for all

listeners, only came to light because of the death of a child.

It raises serious questions about how M.I.5 and M.I.6 treat their intelligence assets,

the people they recruit, and the risks they ask them and their families to take on behalf

of the country.

It's such a crazy world report on, I mean, you are in a hall of mirrors where you know

that literally every person involved was trained in lies, deceit and deception.

You're listening to stories of our times from the times and the Sunday times.

I'm Manvine Rano.

Today, an M.I.6 agents journey from spy to killer.

My name's Gabriel Pogrand.

I'm the Whiteful Editor at the Sunday Times.

And Gabriel, your latest story is astonishing investigation you've done.

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