Boston is being terrorized by a series of seemingly random murders of women. Based on the true story, the film follows the investigators path through several leads before introducing the Strangler as a character. It is seen almost exclusively from the point of view of the investigators who have very few clues to build a case upon.
Wealthy widow Helen Mercer hires a young woman, Gretchen Addison, to act as her personal assistant and companion. Unfortunately, Helen is a poor judge of character, as Gretchen is part of a murderous extortionist duo with her boyfriend, Jay. However, Gretchen has second thoughts when she develops genuine affection for Helen. When Gretchen informs Jay that she wants to call off their plot, he refuses and carries on with the plan. Now both Helen and Gretchen may be in grave danger.
A Marine officer reported as killed in Vietnam, but who was actually a POW, returns home. Instead of being welcomed home, however, he discovers that his father has died, his wife has remarried, his daughter has been adopted, his business has been sold, and his life has completely changed.
