A second probationer is killed at the police college, and the college commander proves obstructive. Harry discovers that his late friend's widow was prescribing him drugs.
A young man is found bound at his neck, wrists and ankles in the same location and in similar circumstances to a case Leo worked on. It is apparent that the cases are both linked, and they begin to look into the murders and find their killer. The widow of an old friend of Harry's asks him to carry out a post mortem on her husband.moreless
Leo has to investigate the death of a student, the daughter of a powerful donor to the university. Is her death related to the theft of the drugs?
When a truck driver accidentally reverses into a wall, he finds a body there and contacts the police. They phone for Sam, who is currently dealing with a break-in at the toxicology lab, and when she arrives at the scene she examines the body, which is around seven years old. They soon discover that he was murdered and begin to look for his killer.moreless
Sam believes that the businessman was killed elsewhere and his body moved. Another of his children is killed. The SIO wants to renew his relationship with Sam. Leo, preoccupied by domestic concerns, is dismissive of Harry's doubts concerning the death of the old woman.
Sam is reunited with an old flame when she investigates the murders of a ruthless businessman and his family. Meanwhile, Harry deals with the seemingly routine death of an elderly woman who fell down some stairs.
Sam is called to the Thames, where a girl's body has been found. It's missing an arm, and the pathologists try to ascertain the connection with the road traffic accident.
Sam and Leo arrive at the scene of an accident, involving six vehicles. They begin to investigate the causes of the crash and attempt to identify all the bodies. A severed arm found at the scene does not appear to belong to any of the victims.