Read the book!
This film as bases on a really great novel written by Mr. Woolrich. Toyled The Black Path of Fear. The film follows the story line pretty well in the beginning, but somewhere in the middle, it takes a 120 degree turn, and has nothing what so ever to do with the novel. Totally amazing. Whoever made the decision to ignore Woolrich's excellent story line, and his patented ending, (usually you say, "I never saw that coming" Wherein in the film the ending was done up hollywood style. This is not a noir film. Unfortunately..
Please find and read this novel. It is worth your time.