You're listening to a podcast from the BBC World Service. This is Hard Talk with me, Stephen Sacker.

Thanks for downloading this edition of the program. I do hope you enjoy it.

My guest today has emerged from the shadows to tell the story of his extraordinary involvement in the violent conflict which engulfed Northern Ireland for three decades.

Willie Carlin was a Catholic brought up in a staunchly nationalist area of the city of Derry.

Despite that, following in the footsteps of his father, he joined the British army and served Queen and Country.

Then he returned to his hometown, But unbeknownst to his

family and community, he returned as a spy, working for the British Intelligence Service,

MI5. Now this was the mid-1970s with the conflict between the Irish Republican Army and the British

military in full swing.

Willie Carlin got a job working as an activist and organiser inside Sinn Féin, the political wing of the IRA.

He worked closely for years with Martin McGuinness, an IRA commander who ultimately embraced the concept of a negotiated peace and political settlement between Northern Ireland's nationalists and unionists.

Eventually, Willie Carlin's cover was blown. He and his family made a dramatic escape from Northern Ireland, and he's been in a form of hiding ever since.

Now he's chosen to tell his secrets.

So how does he justify what he did?

Willie Carling.

Welcome to Hard Toll.

Thank you for having me.

It is actually quite extraordinary having you in the studio,

given that you were an undercover spy in the 70s and the 80s,

an extraordinarily dangerous, sensitive time in Northern Ireland, and you then went into hiding.

You lived in secret.

Why have you now, later in life, decided to come out of the shadows?

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