Marge Brock is a divorced mother of three teenagers trying to make a living in Boston as a researcher. When an author hires her to research unsolved murders, she is grateful for the assignment. However, as she gathers information about a series of unsolved murders in Great Britain and in Boston, she begins to wonder whether one of the members of the circle of friends that she had in Great Britain, and now has in Boston, might be the killer. Her suspicions only increase as she begins to notice that she is being followed, and her apartment is broken into and ransacked. Can she find out who the killer is before she becomes a victim herself?