Greengrass buys a used police car at an auction, where Bernie Scripps recognizes the former racing driver Russell Palmer, who now works for his cousin Keith Hibbert. Hibbert and Palmer are arrested after a brawl at the Aidensfield Arms and have to spend the night in prison at the police station under the watchful eyes of PC Bradley, who has the night watch. During the night Palmer complains of head aches and early next morning he is found dead in his cell. Hibbert accuses PC Bradley of beating Palmer up and thus causing his death. Acting sergeant Rowan has no other option than to launch a full investigation and suspend Bradley. Meanwhile Greengrass has converted his police car into a taxi cab and happens to overhear a little too much on his radio.