Leon Poole looks like your typical hapless film-noir antihero. A war veteran, he was apparently sort of a foul-up as a soldier, known as "Foggy" to his sergeant, who happens to show up at the bank where Leon works as a teller to embarrass him with wartime tales. What worse can happen? How about a bank robbery? Possibly goaded by Sarge's ribbing, Leon decides to play hero and tries to stop the robbers from leaving the bank. He gets knocked on the head for his trouble, but he wins the old sarge's respect.
One problem: Leon's play at heroism is exactly that: a put-on. As a wiretap reveals, he was the inside man on the job. On that evidence, Det. Sam Wagner (Joseph Cotten) leads his team to the Poole apartment. Tipped off by his accomplice to the tap, Poole is armed and ready, firing through the door to wing Wagner's partner Gillespie (Michael Pate). Sam and uniformed flatfoot Denny (Alan Hale Jr.) burst through the door, Sam hitting the floor and firing at a shape in the dark. The shape was Poole's unarmed wife. Leon himself is stunned, strangely submissive yet calmly indignant as he lays Mrs. Poole out on their bed before his arrest. He maintains the same attitude through his trial, and upon his conviction promises Wagner that he'll settle accounts with him someday.