A man is killed in apparently random attack, and suspicion falls on a gang of muggers. Only Detective Sergeant Geraldine Steel thinks this is the work of a more deliberate murderer. Two more victims are discovered, after further seemingly indiscriminate attacks. The muggers are tracked down, with tragic consequences, but does the killer still remain at large? When Geraldine finally manages to track down a witness, she finds her own life is in danger.