When Dr. Edwin Lorrimer, a forensic scientist working at a private laboratory is found killed, Detective Superintendent Adam Dalgliesh is sent to investigate. Dalgliesh had been in the area a few months previously investigating the murder of a young woman found in an abandoned car.

Commander Dalgliesh is called to Norfolk to look into a murder, which he believes has no connection with the case that he is currently working on. But then one of the forensic scientists at Hoggatt's laboratory, who are experts in violent death, is found murdered.