A World War II veteran who thinks he's dying gets mixed up with gangsters.

While traveling to New York by train, Bill Baker, a recently discharged serviceman, meets Vickie North, an aspiring artist from Wisconsin, her young brother Jamie and Louie, a gangster. When Bill cheerfully admits to Louie that he "just got out" after serving as a "tommy gunner," Louie, who spent the entire war in jail, assumes that the wide-eyed veteran is a fellow racketeer and invites him to seek employment with his boss, Tiny McBride. Bill also confesses to Louie that he is a hypochondriac with a hyperactive imagination and suffers from dizzy spells. While roughhousing in his seat with Jamie, Bill is accidentally knocked out by Vickie's falling painting case. Bill wakes up alone in a New York hospital ward and overhears two doctors, standing just outside his bed screen, discussing a patient's fatal heart condition. Concluding that he is the unfortunate soul who only has two weeks to live, Bill leaves the hospital in a daze. Bill then goes to Tiny's bar and, believing that excitement will quicken his death, tries to provoke Louie and the rest of the rough crowd to fight with him. The gangsters, however, refuse to fight, and a despondent Bill is about to jump from the nearest bridge when he becomes dizzy and scared. At that moment, Vickie passes by and, assessing the situation, lectures him about not giving up on life. Taken with the sincere artist, Bill kisses her impetuously and is knocked out by a passing truck driver, who mistakes him for a masher. Bill then wakes up in Vickie's Greenwich Village apartment, where he is made a virtual prisoner by a concerned Vickie and Jamie. When Bill, who has said nothing about his "condition," tells Vickie that he finds her abstract paintings "interesting," she becomes incensed and storms off to attend a street art exhibit. Bill and his romantic competitor, insurance salesman Phil Bright, try to attract attention to Vickie's paintings, but fail. Truly upset, Vickie abandons her exhibit, but confesses to Jamie, who protested their move to New York, that she has no money for a return trip to Wisconsin. After Phil proposes unsuccessfully to Vickie, Bill reveals his situation to Louie and Tiny, and asks Tiny to give him $5,000 in exchange for being named the benficiary on his army life insurance policy. When Tiny learns that the policy is to be paid out in small installments, he angrily rejects the offer, but then suggests a plan whereby he will buy a private insurance policy through a crooked agent that will pay $100,000 upon Bill's death. Bill hesitates, but is soon talked into participating by the persuasive gangsters. Phil, who enjoys the worst sales record in his company, is then chosen as the agent, and he is convinced by Louie to join the scheme. Still certain he is about to die, Bill convinces Louie to pose as an art dealer and buy some of Vickie's paintings with the $5,000 he received from Tiny. When an ecstatic Vickie declares she is staying in New York, however, Bill feels compelled to tell her the truth about Louie. Vickie at first refuses to believe him, but eventually realizes that Jamie belongs back in Wisconsin and makes plans to return. Now in love with Bill, Vickie invites him to Wisconsin, but he insists he must stay in New York. After they enjoy a fun-filled day at the beach, Bill confesses to Vickie that he loves her, but angers her when he turns down her proposal without explanation. Tiny, meanwhile, is growing impatient with Bill and hires his enormous bouncer, Smoky, to fight him in a boxing match. After the fit Bill easily defeats Smoky, Louie tries to exhaust Bill to death through intense exercise. When that fails, Louie forces Bill at gunpoint to a doctor's office and, upon learning the truth about Bill's robust health, drives him to Tiny's. Following them there are Vickie and Jamie, to whom Bill has written a confessional letter. To Bill and Louie's surprise, Tiny welcomes Bill and reveals that he loves Vickie's paintings. When Vickie learns that Tiny is using her art to scare his drunken customers into ordering more alcohol, however, she grabs her paintings and rushes with Jamie to the train station. Bill pursues her there, but is knocked out once again when Vickie angrily hits him with her painting case. At the hospital, Bill proposes to a still upset Vickie, who then learns that Tiny is naming her the beneficiary of Bill's policy on condition she marry him and allow him to keep her paintings. As they drive back to the train station, Vickie finally accepts Bill's proposal with a kiss.