The extraordinary story of what some say is the widest miscarriage of justice in UK legal history as sub-postmasters take on the Post Office.

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 we get inside the story of Sarah Burgess-Boyd, who was just one of hundreds of sub-postmasters charged with theft. We hear first-hand her contemporaneous testimony to her accusers. We also learn about the oldest recognised criminal investigations force in the world - the Post Office

Presenter: Nick Wallis