Journalist Alex Renton is shown a secret document, containing the names and addresses of people signed up to a pro-paedophile group called the Paedophile Information Exchange, or PIE, which was active in the 1970s and 80s.

That’s not all: weeks after getting the membership list Alex meets a contact who gives him bags full of documents, crammed with reports, contact details, letters.

As Alex starts following up on leads; detail of the criminal activities committed by some of PIE’s members, and those connected with them, begins to emerge.

It’s a lot to take in. Alex is not only a journalist, he’s a survivor of child sexual abuse. All of this information about PIE; it feels like a heavy weight to carry. Are children still at risk?

Alex sets off on a dizzying journey into the dark history of the Paedophile Information Exchange and uncovers abuses committed by PIE's members: teachers, clergy, social workers, government advisors.

As Alex finds out more, he starts to wonder: where are all those hundreds of members now?

He meets the former deputy editor of Private Eye, journalist Francis Wheen: he has a long memory for news and a nose for stories that people in power want to keep secret. What does he know about PIE?

Archive credits: Newsnight, BBC, August 1983

Details of organisations offering information and support for victims of child sexual abuse are available at bbc.co.uk/actionline

Presenter: Alex Renton Producer: Caitlin Smith Researchers: Claire Harris and Marisha Currie Executive producers: Gail Champion and Gillian Wheelan Written by Alex Renton, Caitlin Smith, Jack Kibble White and Kirsty Williams Sound designer: Jon Nicholls Theme tune composed by Jeremy Warmsley