During the trial, after the prosecution rests, the defendant, Larry Ballentine, Robert Young takes the stand to tell his side of a tangled murder case.
In flashback, he describes how he began seeing magazine writer Janice Bell, Jane Greer—innocently enough, but feelings developed. Unwilling to break up his marriage to Greta, Janice gets a job transfer. Larry says he will dump Greta and run off with her. But Greta knows and is unwilling to give him up. She tells Larry she's purchased a quarter-interest in a Los Angeles brokerage for him, and gotten them a home in Beverly Hills. The combination of temptation and a heavy guilt trip hung on him is too great, and he abandons Janice without either explanation or goodbye.
At the brokerage, Larry is reprimanded by his business partner, Trenton, for neglecting a rich potential client, but Verna Carlson shows Trenton a copy of a letter she lets Trenton believe was Larry’s work. Verna Carlson, Susan Hayward, is an admitted gold-digger, stringing along Trenton, Tom Powers, while she uses the letter to manipulate him. Larry’s indiscretions threaten Greta, and Verna’s schemes pull both of them deeper into a web of lies. Verna is also quietly steering Larry toward a future she envisions, even as Greta—Greta Ballentine, Rita Johnson—discovers the truth.
Greta finds out about the affair and decides to cut loose from Los Angeles, buying an old Spanish rancho in the mountains. Forced again to choose, Larry tells Verna he is ending their affair, to her bitter disappointment. The ranch is isolated, without phone or mail service, and Larry grows bored while Greta loves the quiet life. Greta wants to build a guest house for an aunt who reviles him, and Larry pretends he can arrange it with a trusted architect from L.A. Under the pretext of calling him, he phones Verna from a general store down the road and arranges a rendezvous.
Larry tells Verna he will run away with her after cleaning out most of Greta's checking account. He writes a large check for Verna to cash, and leaves a farewell note for Greta. Verna meets him as planned, but uncharacteristically returns the check. She has also bought herself a cheap wedding ring, an inducement for him to follow through on his promise to divorce Greta and marry her. Choosing a penniless future with her over another return to Greta, Larry slips the ring onto Verna’s finger.
As they drive to Reno that night an oncoming truck blows a tire and swerves into their path. Verna is killed and burned beyond recognition. Larry wakes up in the hospital, concussed. Verna’s wedding band causes her to be misidentified as Greta. Hatching a plan, he chooses not to correct the error.
Once he recovers, he returns to the ranch to eliminate Greta before she is seen alive. Finding the house empty, he goes to her favorite spot, a cliff by a waterfall. His goodbye note is lying at the top, and Greta’s body at the bottom. He dumps her corpse in the dark pool below the falls.
Depressed, Larry borrows against the estate and tours South America unsuccessfully trying to cheer himself up. In Jamaica, he runs into Janice. They reconcile, and she persuades him to return to Los Angeles. Later, arriving early at her hotel, he sees Trenton go into her room. Eavesdropping, he learns that Trenton believes Verna was blackmailing Larry, who killed her and hid her body on his ranch, and that Trenton had put Janice up to luring him back stateside.
Ultimately, Trenton calls in the police. They find Greta's decomposed body, but assume it is Verna's. The local storekeeper is a witness to Larry and Verna driving away together the day both disappeared. The police buy Trenton's version of events, and Larry is tried for Verna's murder.
While the jury deliberates, Janice visits, believing in his innocence and seeking forgiveness. She promises to wait for him. He says there won’t be any waiting, and that the jury does not matter, as he has passed judgment on himself. Back in court, as the verdict begins to be read, Larry rushes to an open 12th floor window. Before he can jump he is shot dead by a courtroom guard. The bailiff then reads the verdict: Not guilty.
