This time the rot is inside Scotland Yard. Detective Sergeant William Warwick is sent undercover to expose corruption within the Metropolitan Police, and his inquiries settle on DS Jerry Summers, a young officer whose lifestyle is far too lavish for a policeman’s pay. When Summers grows close to a WPC on William’s own team, the whole operation wobbles, and the deeper William digs, the more it looks as though the corruption reaches higher than anyone imagined. Archer turns the series inward with relish, and suspicion falls in the most uncomfortable places.