The drifter Isabelle 'Isa' Tostin travels to Lille to meet her former boyfriend but he has traveled to Belgium. She looks for a job since she has no money in a clothing factory, and befriends Marie Thomas, who also works in the factory. Despite their differences of behavior, they become friends. Marie is taking care of an apartment, whose owners have had a car accident, and Isa stays with her in the place until the day that a tragedy happens.