After the introduction of a new computer system in the early 2000s, the Post Office began using its data to accuse sub-postmasters of falsifying accounts and stealing money. Many were fired and financially ruined; others were prosecuted and even put behind bars.

In this ten-part series, journalist Nick Wallis, gets right to the heart of the story, as he talks to those whose lives were shattered and follows the twists and turns of a David and Goliath battle as the sub-postmasters tried to fight back.

Today, Alan Bates and the sub-postmasters reach the High Court, and the Post Office’s secrets start to tumble out one by one.

Presenter: Nick WallisProducer: Robert NicholsonExecutive Producer: David PrestWith Sound Design from Emma Barnaby and Story Editing from Alexis Hood.A Whistledown production for BBC Radio 4