Fanfan leaves his friend Charles and thinks he can be accommodated by his friend, Joss. However, at the same time, Joss abandons the marital home. Fanfan and Joss have only to knock on the door of Manu, Fanfan's sister, who gathers them until Mytch, Manu's companion, throws everyone out. The three young women find themselves in the street and continue their run, while their lovers gang up to track them down. The mini-war of the sexes will flare up.

Fanfan quitte Charles et pense pouvoir être hébergée par son amie, Joss. Sauf, qu’au même moment, Joss abandonne le domicile conjugal (son mari, Paul et sa fille, Lise). Fanfan et Joss n’ont plus qu’à aller frapper à la porte de Manu (la sœur de Fanfan) qui les recueille jusqu’à ce que… Mytch (le copain de Manu) ne mette tout le monde à la porte.