Jane Birkin said she asked
Jean-Louis Trintignant to hit her for real in a scene. "My first scene was rather difficult: I was naked in front of Trintignant in the hotel room. Moreover, in the script, it was written that he was kissing my breasts. I thought: My God, he has fallen badly! I was ashamed. Only one thing helped me: he had to slap me and make me fall on the floor. Now, when you get a slap on the mouth, your mouth becomes like cotton when you say the next lines. I had to say, 'You have a little bike in your head'. My mouth hurt and I said it in a cottony way. Unfortunately, we had to double the scene because of the camera noise, and I couldn't do it as well. I would have had to get a grip on myself! Today, I wouldn't hesitate to do it. Trintignant was nice, he didn't want to hurt me. I wanted him to hurt me, I begged him to hit me," Birkin recalled.