Pathologist Dr. Sam Ryan re-examines evidence of an unsolved murder from the past to help trace a recent murderer of a young wife and her lover. The couple had planned to run off together, but the night before their departure, the wife is killed. The evidence points to her husband, except that the murder was very similar to one committed a year before. Then the boyfriend is murdered and the case against the husband seems strengthened. But this murder, too, is similar to another in the unsolved file and a faint bruise on both victims could be enough to rule out the husband as a prime suspect.