Actor Philippe Martin plans to meet Yvonne, his married girlfriend, in the afternoon cinema where they can neck and be together in the dark. Martin arrives late, and the feature has started, so he goes to the seats where they planned to meet. Soon he kisses the girl next to him, but it's Monique Perelin and not Yvonne as he'd expected. Indignation follows a slap to his face and he's eventually arrested and put on trial. Philippe enters his own defense, much to the delight of the spectators, and he winds up being sentenced to three days in jail or a hefty fine. Monique offers to pay his fine when he admits to not having the money, and from there it's continual interference of every nature (mostly by her father) as they try to meet again.