An investigation into past corruption in one of the country's biggest police forces. Panorama tells the inside story of how detectives who served in the West Midlands Drug Squad framed suspects and misappropriated drugs and money. For years the West Midlands police has been dogged by allegations of wrongdoing, from the railroading of the Birmingham Six to the revelation that some members of the Serious Crime Squad were torturing suspects.

Peter Marshall reports on the difficulties the force has had in trying to stop corruption and the troubles experienced by officers who have spoken out against their colleagues, only to see some of them escape justice.

(Note: as Panorama is topical and likely to react to events in the news, its subject matter may change)