A D.I. from Sheffield has information involving a big operation to catch a gang of five villains nicking heavy plant machinery. The snout the D.I. was using turns out to be one of Sun Hill's informants, and Ch. Supt. Brownlow has words at the Super's meeting after the operation. D.I. Burnside is told to take a backseat to the CID operation. D.C. Dashwood raids an empty house, and D.C. Carver can't get into the house he goes to. Two uniformed officers accompanying D.S Roach are assaulted.

Boyden is unsure as to the cause of death when a man's body is found in a car, poisoned by alcohol and exhaust fumes. Is it really a straightforward suicide?