Two days before Christmas, after his boss, J. L. McKissack, refuses his request for a raise, Fidelity Trust bank teller Johnny Dalton argues over lunch with his longtime girl friend, Mildred Goodhew, about their marriage plans. Mildred, who is also a teller, is tired of waiting, but Johnny insists he cannot marry until he is making more money. When waiter Emil Keck urges the conservative Johnny to "live dangerously," a frustrated Mildred applauds the advice and storms out of the restaurant. Moments later, as Johnny is returning to the bank, he sees two thugs beating up a third man and comes to the rescue. The beating victim, Hot Horse Harris, is so grateful to Johnny that he takes him to his betting parlor in the back of a shirt store and gives him a $1,000 bill. Johnny protests the gift, but before he can reject the money, Hot Horse bets it on a horse race. Johnny wins $5,000, then impulsively allows Hot Horse to bet the whole amount on another race. That bet also pays off, and before long, Johnny has accumulated $60,000 in winnings, $40,000 of which Hot Horse pays him immediately. The now-flush Johnny rushes to see Emil, who assumes that Johnny took his advice and turned to crime. Emil nevertheless helps Johnny buy a car and mink coat for Mildred. At the bank, meanwhile, a still angry Mildred accepts a date from Bob Pulsifer, the bank president's playboy son. When Johnny finally returns to work, he finds McKissack informing the bank staff about a $75,000 embezzlement, which bond detectives are already investigating. Fearing that he will be implicated, Johnny leaves in a panic and takes Emil to the shirt shop to collect his remaining $20,000. To his dismay, the bookmaking operation has disappeared, adding to Emil's doubts. The two then go to Johnny's apartment, which is separated from Mildred's by a thin wall. Overhearing the delivery of Mildred's mink coat, Johnny and Emil dismantle a door that connects the two apartments, and as Mildred is showering, Johnny slips in and removes the coat from its Christmas box. He and Emil then try to stuff the money into Johnny's shower head, but succeed only in flooding the apartment. After the apartment manager informs Johnny that a detective has been asking questions about him, Emil offers to deposit the money under his name in an out-of-the-way bank. Mildred, meanwhile, has gotten drunk during her date with Bob, and while he is dropping her off, he finds the discarded fur coat tag on her floor and becomes suspicious. The next day, Emil arrives at Fidelity Trust posing as a wealthy prospective depositer. As part of his ploy, Emil insists on speaking with Bob's semi-retired father R. B. and the banker is so impressed that he later requests to meet Emil in order to solicit a charitable donation. While Emil rushes to the posh hotel where he is supposed to be residing, one of Hot Horse's men, dressed as Santa Claus, leaves $20,000 on Johnny's doorstep. Mildred finds it first, however, and after someone from the fur store calls her about the returned coat, she concludes that Johnny is the embezzler. Mildred tracks Johnny to Emil's hotel suite and demands an explanation. Johnny reveals all, but Mildred refuses to believe his story, and Johnny stomps off. Emil, however, convinces Mildred that Johnny embezzled only to please her. Guilt-ridden, Mildred takes the $20,000 to Bob and offers to "do anything," including marrying him, if he does not press charges against Johnny. Horrified by the thought of marriage, Bob instead calls the police as Mildred drives off in his car. Mildred then picks up Johnny and, having forgiven each other, they decide to marry that night. The police stop them first, however, and, to Johnny's astonishment, arrest Mildred for the embezzling. R. B. later explains to Johnny that while the police deduced the source of his cash, an audit of the bank books showed that the missing money came from Mildred's account. Still posing as a millionaire, Emil insists that they search the bank on Mildred's behalf, and they soon discover that Mildred's adding machine is defective. R. B. then accidentally sets off the alarm, summoning the police, who refuse to believe that R. B. owns the bank and try to arrest him. After Bob shows up, R. B. finally proves his identity, and Mildred and Johnny are cleared of all suspicion. Later, a just-married Johnny and Mildred pose for pictures at Emil's restaurant while declaring to a man with a notepad their plans to spend their winnings buying an orange ranch, which Emil is to help them run. After the man reveals he is from the Internal Revenue Service, the trio dashes off in their new car.