The story was based on a 1927 crime perpetrated by a married Queens woman and her lover. Ruth (Brown) Snyder persuaded her boyfriend, Judd Gray, to kill her husband Albert after having her spouse take out a big insurance policy—with a double-indemnity clause. The murderers were quickly identified and arrested.
"Double indemnity" refers to a clause in certain life insurance policies where the insuring company agrees to pay twice the standard amount in cases of accidental death.
Walter Neff (MacMurray) is a successful insurance salesman for Pacific All-Risk returning to his office building in downtown Los Angeles late one night. Neff, clearly in pain, sits down at his desk and tells the whole story into a Dictaphone for his colleague Barton Keyes (Robinson), a claims adjuster.
It is the story of how he meets the sultry Phyllis Dietrichson (Stanwyck) during a routine house call to renew an automobile insurance policy for her husband. A flirtation develops, at least until Neff hears Phyllis wonder how she could take out a policy on her husband's life without him knowing it. Neff knows she means murder and wants no part of it.
Phyllis pursues Neff to his own home, and persuades him that the two of them, together, should kill her husband. Neff knows all the tricks of his trade and comes up with a plan in which Phyllis's husband will die an unlikely death, in this case being thrown from a train. Pacific All-Risk will therefore be required, by the "double indemnity" clause in the insurance policy, to pay the widow twice the normal amount.
Keyes, a tenacious investigator, does not suspect foul play at first, but eventually concludes that the Dietrichson woman and an unknown accomplice must be behind the husband's death. He has no reason to be suspicious of Neff, someone he has worked with for quite some time and admires.
Neff is not only worried about Keyes. The victim's daughter, Lola (Jean Heather), comes to him convinced that her stepmother Phyllis is behind her father's death because Lola's mother also died under suspicious circumstances when Phyllis was her nurse. Neff begins to care about what might happen to Lola, both of whose parents have been murdered.
Then he learns Phyllis is seeing Lola's boyfriend behind his back. Trying to save himself and no longer caring about the money, Neff believes the only way out is to make the police think Phyllis and Lola's boyfriend did the murder, which is what Keyes now believes anyway. However, when Neff and Phyllis meet, she tells him she has been seeing Lola's boyfriend only to provoke him into killing the suspicious Lola in a jealous rage. Neff, now wholly disgusted, is about to kill Phyllis when she shoots him first. Neff is badly wounded but still standing and walks towards her, telling her to shoot again. Phyllis does not shoot and he takes the gun from her. She says she never loved him or anyone else and had been using him all along, "until a minute ago, when I couldn't fire that second shot." Neff coldly says he does not believe this new ploy. Phyllis hugs him tightly but then pulls away and looks up at him, startled that he has not responded. Neff says "Goodbye, baby," then shoots and kills her.
Neff drives to his office where he dictates his full confession to Keyes, who arrives and hears enough of the confession to understand everything. Neff tells Keyes he is going to Mexico rather than face a death sentence but collapses to the floor before he can reach the elevator.
Other cast
A contemporary (1944) review of the film in The New York Times was not positive. Film critic Bosley Crowther found Edward G. Robinson's supporting role excellent but also wrote, "Such folks as delight in murder stories for their academic elegance alone should find this one steadily diverting, despite its monotonous pace and length. Indeed, the fans of James M. Cain's tough fiction might gloat over it with gleaming joy.
Double Indemnity is an excellent example of a genre of films called film noir. Its plot and style contains almost all the elements that make up classic film noir:
An Indian film, Jism, was also inspired by the film.
Double Indemnity is one of the films parodied in the 1993 movie Fatal Instinct; the hero's wife conspires to have him shot on a moving train and fall into a lake so that she can collect on his insurance, which has a "triple indemnity" rider.
The following exchange was one of 400 nominated quotes in the American Film Institute's 100 Years... 100 Movie Quotes list of the best film quotes in American film history: