On Christmas Eve, Greg, a solitary and taciturn police officer, doesn't hesitate to leave his daughter behind to go on a mission. To teach him a lesson, Santa Claus decides to grant his daughter's wish: that her father looks like Richard Silestone, the good-natured and heavily indebted family man from the beloved Christmas movie she adores. While Greg is sent into this improbable world, Richard accidentally lands in the real world and both men realize they have no choice but to complete each other's missions to reclaim their respective lives.

Jeanne, a young woman of 22, recounts the last moments of her life in a letter addressed to her parents. On the path to accepting her trans-identity, she will meet Franck, a seemingly xenophobic man, whose confidante she will unwillingly become, to the point of no return.

Anna is a young aspiring actress. Living in a small and old apartment in the projects and failing all her castings next to more talented young girls, she dreams of being someone else and living another life. During a movie casting, she steals an expensive purse belonging to one of the contestants. Inside of it, she finds a letter informing its rightful owner that her biological parents have revealed their identities. This is the opportunity for Anna to play a role hopefully rewarded with a cash prize. Unfortunately for Anna, she is going to learn the hard way that it is dangerous to play with someone else's identity.

On the northern outskirts of Paris, where housing projects rise out of fields, Adja, 18, burns with the desire to live intensely. While her brother breaks out as a pro soccer player, her best friend blows up as an influencer on social media, and her mother struggles to save her hometown in Senegal, Adja has only a blurred vision of her future. With Arthur, who becomes more than a friend, her political and environmental awareness rises, and Adja joins the fight of her generation.