This episode reveals what happens when a police officer who is meant to be investigating a crime turns out to be the man who committed it. The unprecedented access takes viewers behind the scenes into an allegation of police corruption. Cameras follow all of the twists and turns of a unique and gripping investigation as it unfolds, as detectives from the Major Crime Unit track down, arrest and then charge their suspect. Police officers from across Bedfordshire have to come to terms with the fact that one of their own, a colleague and someone some regard as a friend, is a corrupt cop. This is real-life drama at its most intense.

A man lies dead in a park in Peterborough. The position of his body raises intense suspicions but rigor mortis has already set in and the trail of evidence is going cold. Who is the victim and how did he come to be dumped overnight in open ground? Detectives are called in to investigate. Cameras follow every extraordinary twist and turn of the investigation as the job of working out this real whodunnit becomes the priority for the Major Crime Unit. Bafta Award-nominated 24 Hours in Police Custody follows Bedfordshire, Cambridgeshire and Hertfordshire Police's detective work around the clock in forensic detail as officers race against time to investigate major crimes, disentangle evidence and build a case, which they then put to their suspects in interview. This is real-life crime drama at its most intense.