A car swerves through downtown streets at night. The driver stumbles to the office of the Pacific All Risk Insurance Company and begins to record his confession about killing a man named Dietrichson. He flashes back to the beginning of the ordeal, when he first met the Dietrichsons.
He, Walter Neff,
was
an insurance salesman who renewed Mr.
Dietrichson's policy at home. Walter was attracted to the man's wife
Phyllis, although her manner was cold and sarcastic. She asked Walter
about accident insurance for her wealthy husband. Walter accused her of
trying to get him to kill her husband and refused. At his apartment,
Phyllis told Walter how abusive her husband was, so Walter agreed to kill
Dietrichson. Walter tricked Dietrichson into signing the accident
insurance policy which insured Dietrichson's life for $50,000--an amount
to be doubled in case he had a fatal accident on a train. Walter also gave
Lola, Dietrichson's daughter from his late, first wife, a ride to town
where she secretly met her boyfriend Nino Zachette.
Several weeks
later, Dietrichson agreed to take the train to attend a
college reunion. Walter killed Dietrichson and posed as as him and got on
the train. Later, Walter jumped off the train and with Phyllis' help,
placed Dietrichson's body on the tracks to make it look like Dietrichson
had fallen off the train to his death.
Walter's boss
Keyes
told Walter that he suspected that Dietrichson's
death was no accident, but a murder committed by Phyllis and her lover,
Nino Zachette. Walter went to Phyllis' house and she shot him. He shot her
dead and drove to the insurance office to record his confession.
Now Keyes watches him. Walter collapses.