A helicopter on its way to an oil rig goes down with twenty workers on board. Called in to supervise the post-mortems, Professor Sam Ryan begins to piece together how the crash happened.

A helicopter on its way to an oil rig goes down with twenty workers on board. Called in to supervise the post-mortems, Professor Sam Ryan begins to piece together how the crash happened.

Brian McNally is a one-time criminal with a major problem. The day after he is badly beaten by gangster Mike Georghiou, McNally finds Georghiou's strangled body at his business. He's convinced that Mike's brother Tony, also a gangster known for his violent streak, will come after him so he gets Sam Ryan to prove that he couldn't have been the killer. Sam does so but when McNally's body is found at the foot of a building, a supposed suicide, she feels she has somehow contributed to his death. What Sam doesn't realize is the is not only going up against organized crime but coppers who've acted as judge, jury and executioner.

Brian McNally is a one-time criminal with a major problem. The day after he is badly beaten by gangster Mike Georghiou, McNally finds Georghiou's strangled body at his business. He's convinced that Mike's brother Tony, also a gangster known for his violent streak, will come after him so he gets Sam Ryan to prove that he couldn't have been the killer. Sam does so but when McNally's body is found at the foot of a building, a supposed suicide, she feels she has somehow contributed to his death. What Sam doesn't realize is the is not only going up against organized crime but coppers who've acted as judge, jury and executioner.

Sam is reunited with newly promoted DCI Michael Connor when they investigate a fire in a cinema. Sam manages to identify all but one of the 12 victims, body #10. As she gathers more information, including the use of a facial reconstruction, she comes to believe that body #10 is in fact someone who was supposed to have been killed years before and for which Chris Caldwell was convicted of murder. Sam becomes attracted to Caldwell and manages to get him set free, but when others are subsequently murdered, Connor does not believe Caldwell is quite as innocent as Sam believes.

Sam is reunited with newly promoted DCI Michael Connor when they investigate a fire in a cinema. Sam manages to identify all but one of the 12 victims, body #10. As she gathers more information, including the use of a facial reconstruction, she comes to believe that body #10 is in fact someone who was supposed to have been killed years before and for which Chris Caldwell was convicted of murder. Sam becomes attracted to Caldwell and manages to get him set free, but when others are subsequently murdered, Connor does not believe Caldwell is quite as innocent as Sam believes.