In Northern Ireland, from the late 70s to the early 90s, the IRA killed over 40 alleged informers.

But the man who often found, tortured and sometimes killed these people on behalf of the IRA

was himself an informer, a secret British army agent with the codename Stakeknife.

Who gets to play God? And why me? Why my family?

When lies are still being told to this day, who do you believe?

I wouldn't even know where to start.

And I'm with the IRA.

Steakknife.

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Hello, today's show is haunted by murderers and the murdered, by dreams of

futures that fail to materialise, by the shadows of lost potential.

And if I'm not convincing you that all that is an entertaining listen, thankfully I'll be

aided by a writer who has gripped the world with such ingredients over decades.

We start with a centenary of one of the leading figures in crime fiction, P.D. James.

Although sharp and prolific to the end,

she died in 2014 at the age of 94 and produced 19 works of fiction

the last as recently as 2008.

P.D. James was something of a late bloomer

and seemingly emerged onto the scene as a perfectly formed writer.

She hit the ground running with characters on the run.

Here she is talking in 2001 about her attitude to her craft.

...