Plot
Polly Parrish (Ginger Rogers) is a salesgirl at the department store John B. Merlin and Son in New York City. Hired as temporary help for the Christmas season, she receives her dismissal notice as the season comes to a close. On her way home, she sees a stranger leaving a baby on the steps of an orphanage. Fearing exposure to the cold will harm the baby, Polly takes it inside. Polly is charmed by the baby, but shocked when the orphanage staff believe she is the mother and insist she can continue to care for her child with their help. She leaves the baby, but not before accidentally informing the staff where she works.
The orphanage director searches out David Merlin (David Niven), the playboy son of the store's owner J.B. Merlin (Charles Coburn), and explains a woman abandoned her child because his store laid her off, requesting he re-hire her. David is sympathetic to the "unwed mother" and arranges for her to get her job back, with a permanent position and a raise, while promising a wonderful Christmas present will be delivered to her home later in the evening. The gift turns out to be the baby, delivered by the orphanage attendants.
Polly had made arrangements with Freddie, a stockboy at the department store, to enter a dance competition, so she takes the baby to David's home and leaves the child with his butler. David is enraged and, after being thrown out of the dance competition with the baby, is forced to wait for Polly's return. When she does, he threatens that she has the choice to either take care of the child properly, or find herself fired, denied a recommendation, and blacklisted by every employer in the city.
Mrs. Weiss (Ferike Boros), Polly's landlady, provides baby equipment and offers to take care of the boy when Polly is at work. Unable to convince anyone that she is not the mother, and threatened by David with loss of her job if she doesn't assume that role, Polly gives up, names the baby "John", and starts raising the child.
David continues to check in on Polly and the baby, and all three find themselves very compatible. David's involvement with Polly gradually turns into fondness, and he finds himself reaching out to interact with her more and more, bringing her and the child small gifts, stopping for visits, and talking together. Freddie's misconception of the situation between David and Polly is worsened when his own seniority warrants his promotion, which he credits to Polly putting in a good word for him with David.
New Year's Eve has arrived and David has no date. To save face, David turns to Polly. He orders clothes to be sent from the store and takes her to a party, playing a prank on the other guests that Polly cannot speak English and David must act as her interpreter. David spends the party pouting and jealous that this ruse does not prevent Polly from receiving male attention. The pair leave and have a romantic whirlwind of an evening, dampened only by the recollection of baby John, whose existence makes David hesitate. Although David is falling for Polly, he is not ready to commit to a woman with a baby.
An embittered Freddie attempts to blackmail David by sending an anonymous note to David's father, J.B., informing him that David has a secret child. J.B. is delighted with this news. He has long desired for David to settle down and provide him with a grandson. J.B. stalks his son until he sees David meet up with Polly and baby John.
Polly is mirthful to realize the tables are turned and David is now in the same frustrating position she was: His father is wholly convinced John is David's baby, and will not believe any of David's protests to the contrary.
J.B. demands David marry Polly immediately, and threatens that if David doesn't, J.B. will use legal means to seize custody of his supposed grandchild. David rushes to warn Polly about the threat and insist she produce the baby's real father (whom he has long been jealous of) to prove to J.B. that David is not the father. David ends up wounding and insulting Polly when he derides his father's demand that he marry her as ridiculous, as he does not relish the idea of a "ready-made family". He immediately regrets his words, but Polly makes him leave.
Polly is anxious over J.B.'s threat to bring in lawyers and investigate, since she has grown to love baby John and this will expose that she is not his mother. She decides to flee, but the landlady proposes an alternative solution. Polly visits J.B. with her landlady's adult son posing as her husband. A crushed J.B. is about to accept he misunderstood the situation, when David rushes in, dragging Freddie, whom David has bribed into saying is the father of the baby.
In the chaotic results of this interaction, with Freddie breaking and declaring David the father, David attacking the landlady's son in jealousy, and J.B. now wholly convinced David is the father, Polly disappears and tries to flee with the baby.
Distraught and terrified he has lost Polly and baby John forever, David goes after her desperately. When he finds her, David confesses his love and declares to his father that he is baby John's father, and he intends to marry Polly that very night. A touched Polly asks if he still believes she's the mother of that baby. He replies "of course" and she responds "ha-ha", to his confusion. [3]
