When the Fabre family move into their dream house with wonderful neighbors, everything seems perfect except for one thing – the youngest child Ludovic wishes to live as a girl; while he was assigned male at birth, he feels that he is a girl and wants to live as a female. The rest of the family humor him as best they can, rationalizing that Ludovic is only trying to find his identity and will soon be over it .
Trouble begins when Ludovic befriends Jérôme, the son of her father's boss, and expresses a desire to marry him when Ludovic is finally a girl. When visiting Jérôme's house, Ludovic enters his sister's room and puts on one of her dresses, not realizing that the sister is deceased and the room was merely kept in memory of her. Jérôme's mother sees this and she and the rest of the neighbors are horrified. The community turns against Ludovic and, by extension, the rest of the Fabre family. After Ludovic stands in as Snow White in a school play, the parents of the other students send in a petition to have her expelled. Ludovic's father, under strain as an employee of Jérôme's father, is unable to cope and causes conflict within the family. After a particularly bad argument, Ludovic attempts to mend the situation by hiding in a freezer to commit suicide. She is found in time and allowed to wear a skirt to a neighborhood party. While the other neighbors greet her warmly, Ludo's father gets fired the next day and finds his house spray-painted with graffiti. Ludo runs out of the house, distraught. Hanna, Ludovic's mother, blames her for everything that has gone wrong. She wants to set Ludo straight, so she cuts her hair to make her look like her brothers. Ludo resents her mother for doing this, ultimately deciding that she wants to live with her grandmother.
When Ludo and her grandmother go visit her parents one weekend, the father announces that he has a new job, but it is out of town and they have to move.
At their new house, Ludovic is befriended by Christine "Chris" Delvigne, a young girl who prefers to be seen as a boy. Chris' mother invites Ludovic to Chris' dress-up birthday party, which Ludo attends in a musketeer outfit. Chris, unhappy in a princess outfit, asks Ludo to swap and has the other young party guests force Ludo to do so upon refusal. When Ludovic's mother sees her in the dress, she fears that their troubles are beginning again and lashes out by hitting Ludo until the other party guests restrain her.
Hanna follows Ludovic to a billboard where she is shocked to see Ludo in the picture, running away with Pam, the protagonist of a program he used to watch. When she tries to follow, she falls through the ground and awakens at home. She and Ludovic's father assure Ludo that he may wear skirts if she wishes. In turn, she assures her mother that she never really intended to run away with Pam.
Although internationally presented as a Belgian film because of the nationality of Berliner, its director and co-screenwriter, the film is an international co-production between companies in Belgium, the United Kingdom and France – the majority of the production work was done by the French independent film house Haut et Court and the shooting took place south of Paris, France, near the commune of Évry.
The color timing in the film is significant: it changes as parents exit from the school play, switching to cold blue tones.
In the United States the film received an R rating by the Motion Picture Association of America, an unusual decision because the film has minimal sexual content, minimal violence, and mild language. Those opposed to the rating believe that the rating was the result of transphobia.
The film won the Golden Globe Award for Best Foreign Language Film. It also won the Crystal Globe award at the Karlovy Vary International Film Festival.