Two young women, Françoise Margot Abascal and Catherine Grace de Capitani, move to Paris to work at the PTT. They join a training group with several others, including a man who longs to return to Martinique. The training is rough and the promised “dream loft” is only a cramped, dirty room. During training, Catherine is approached by a trainer who wants to sleep with her, but she refuses; that trainer later rapes another candidate. The two friends faint, but on their first day at work, their colleague Carole Zabou Breitman sets a trap out of jealousy toward Catherine's relationship with their line manager. Catherine ends up assigned to the sorting office as punishment for a fabricated theft.
Even after passing the training, their superiors still press for sex; Catherine quickly realises this and seduces her chief inspector, Ivan Claude Rich. She is promoted, while Carole's machinations have consequences for the pair. The two are evicted from their apartment and, over dinner in a restaurant, Catherine explains she is on the social services' blacklist, which means they need a cheap apartment—Françoise may have to move. Françoise later sees a man dining with a child from another table, and they exchange glances. When Françoise visits the social welfare office, the official offers her an apartment but only if she sleeps with him, which she refuses. After telling Catherine, Catherine heads to the social services to seduce the civil servant, and the two end up securing the lease.
Françoise then falls for a man she meets while working at the counter. This man, André Patrick Chesnais, introduces her to his friend Bernard Michel Sardou, a senior civil servant at the Ministry of Post and Telecommunications. Bernard convinces André to let Françoise stay at his place for the night, but he tries to press for sex; she runs away. Back home, she discovers André sleeping with Catherine. Hearing this, Catherine encourages Françoise to return to Bernard's house, and the gambit pays off: Françoise is quickly promoted to the ministry.
The Post Minister François Loubeau Thierry Lhermitte fears being overlooked by the public and the press. Françoise suggests a publicity stunt: a trip to the DOM-TOM to attract journalistic attention. At the airport, there are no journalists, while another minister's trip garners attention. Loubeau cancels the visit and heads back to the ministry, only to learn that Françoise is part of the team. He goes to Martinique with her on a planned holiday. On the island, they find a quiet beach until a delinquent steals their car, forcing them to walk to find help. They locate a dispensary where the doctor calls the Prefecture, with Loubeau presenting himself as the Post Minister. The trip being uncertain, the prefect and doctor doubt his identity, while a postal van arrives with deliveries. The postman stops, and the couple hijack the van; he agrees to drive them only if they share the parcels.
Waiting for the next move, they learn the supposed meeting they are chasing is connected to Martinique's independence movement, which is also seeking media visibility. Françoise suggests that Loubeau shoot a video portraying himself as kidnapped by the independence movement to generate headlines, and the postman agrees if promoted to Regional Director. The tactic works, turning Loubeau into a celebrated figure, while the independence activists gain media traction. Later, Loubeau and Françoise have sex, and upon returning to Paris, Françoise becomes Post Minister. She visits the Post Office where she once worked; her former colleagues are promoted, while Carole Poteau has been sent to the sorting office. Françoise visits the Inspector, the young man from Martinique, to share the news that he can return as Assistant Director. She then goes to see her friend Catherine [Grace de Capitani] now Director, who invites a new employee to spend the weekend with her in Trouville. Finally, Françoise reveals her plans are taking her to the Élysée Palace, where she is welcomed as she steps inside.
