I wanted to like this more, but I couldn't. Two shifting narrators and I didn't like either one of them. Also the concept of a good person being psychologically coerced into an evil action by a sociopath has been done better. Specifically, I could not help but compare this novel unfavorably to James M. Cain's Double Indemnity which burns white hot and leaves the reader shaken and stunned. In Cain's brilliant noir masterpiece we are propelled, squirming and almost afraid to continue, through the anguished and paranoid thoughts of the protagonist and chilled by a villain as dark and psychopathic as they come. There is even a plot similarity in the investigator on the hunt but he is so much more effective in Cain's novel. Read Double Indemnity instead. There is no sense of urgency in Highsmith's story as the narration drifts back and forth between a gutless protagonist intent on wallowing in self doubt and guilt and a whiny villain who is drunk most of the time. I found myself waiting for an showdown that never really happened and an ending that was a total dud.