Francis and Marie first meet Nicolas at a dinner party, where they both feign lack of interest in him. Over the next couple of weeks, the three form a close friendship, meeting up regularly and even sleeping together in the same bed. However, it is clear that both Marie and Francis have an interest in Nicolas beyond friendship. Francis is unhappy when Nicolas invites Marie to the theater. Marie is visibly disappointed when she arrives at a Vietnamese restaurant with Nicolas after the play, finds Francis dining with several friends, and watches Nicolas take a seat at the end of the table furthest from her. Both interpret Nicolas’ actions as signs of intimacy and affection: Nicolas eats a cherry from Francis’ hand; Nicolas tells Marie he loves her and also loves Francis. Their feelings lead to competition for Nicolas’ affections, evidenced by their rivalry over the gifts they buy for his birthday.
The relationship culminates in a trip to the vacation home of Nicolas’ aunt. Marie becomes jealous when Nicolas feeds Francis a marshmallow, telling him to eat it slowly like a ‘striptease’, and she goes to bed early. The next morning, she wakes up alone and observes the two frolicking together in the distance. She decides to leave, but Francis chases after her and the two end up wrestling on the ground. Nicolas is not impressed and decides to leave, saying they can love him or leave him. On returning from the trip, neither sees Nicolas. Each leaves him a voicemail message and Marie writes him a love letter. Eventually, Francis meets Nicolas and pours out his feelings, telling him he loves him and wants to kiss him. Nicolas responds: “How could you think I was gay?”, leaving Francis devastated. Later, Marie catches up with Nicolas in the street and first tells him the letter she sent was meant for a female friend accidentally switched with an academic essay she intended for him. Nicolas asks Marie if this female friend is her lover or her ex, which Marie confusedly denies. As Nicolas goes to leave, claiming to have left something on the stove, she asks how he would feel if she had intended the poem for him. He says he would still have something on the stove.
After a year, Francis and Marie have re-established their friendship. At a party they repulse an attempt by Nicolas to greet them. In the final scene, they both catch the eye of another party guest and together head for him.