In 2022, journalist Alex Renton told the story of sexual abuse and cover up in Britain’s elite schools, including his own. After the Radio 4 series aired, his inbox exploded; with people sharing their personal accounts of abuse.

Last spring, and anothr email. This one came with an attachment: a scanned copy of a membership list for a pro-paedophile campaign group active in the 1970s and 80s. The group's name was the Paedophile Information Exchange, or PIE for short.

The PIE List sets Alex - himself a survivor of child sexual abuse - on a dizzying journey into the group’s dark history.

As he digs further, a source gets in touch; could Alex travel to meet him? During that meeting he hands him other secret documents, which build a picture of the criminal activities of some of PIE’s members: teachers, clergymen, social workers, government advisors.

Alex begins to wonder: where are all those hundreds of PIE members now? Are children still at risk?

Presenter: Alex Renton