The Postman Always Rings Twice is one of James M. Cain's novels that was made into a movie as was Double Indemnity. Lana Turner as the wife and John Garfield as the drifter starred in The Postman, which came out in 1946. They plot to murder her husband and then must live with the consequences. I remember seeing the movie when I was in high school, but don't remember much about it other than a lot of publicity building up to the movie release. More on this at imdb.com/title/tt0038854.
Double Indemnity came out in 1944, starring Fred McMurray and Barbara Stanwyck and Edward G. Robinson, directed by Billy Wilder, screenplay by Billy Wilder and Raymond Chandler, the writer of the Philip Marlowe detective books. An insurance rep lets himself be talked into a murder/insurance fraud scheme that arouses an insurance investigor's suspicions. Robinson is the investigator, McMurray the insurance salesman, and Stanwyck the wife of Actor Tom Powers, who is tricked into signing a double indemnity policy before he is killed. I don't remember much about this movie, either, it's been a long time. I'll have to check them out and watch them again. And more on this at imdb.com/title/tt0036775.
When I read about Paul Cain on davycrockettsalmanack.blogspot.com I thought of James M. Cain, so I went to Wikipedia, http://en.wikipedia.org/wiki/James_M_Cain, and reviewed his writings. He also wrote Mildred Pierce, which was also made into a movie, a boring movie in my estimation. I remember reading his Serenade in a pocket book edition, as I recall, but have no idea what it was about.
Just yesterday, James M. Cain was mentioned in davidcranmer.blogspot.com (The Education of a Pulp Writer) in connection with the latest Beat to a Pulp story.