In Paris, an American widower grappling with his wife's recent suicide, strikes up a chance encounter with a young Parisian woman while apartment hunting. The man, consumed by grief and anger, proposes an intense and anonymous sexual relationship, setting strict boundaries that forbid the exchange of personal information. The woman, curious and intrigued, agrees to his terms. The two begin meeting regularly in the empty apartment, where their interactions are raw, primal, and devoid of emotional commitments. This arrangement, however, hides the deeper and more complex emotions that begin surfacing within both individuals.

As the relationship evolves, the emotional strains start taking their toll. The American's unresolved anguish clashes with the woman's own journey towards adulthood and self-discovery. She continues her life outside the apartment and becomes more entangled with her filmmaker fiancé, who is working on a project about her. The boundaries that were initially set up in their secret relationship start to blur, leading to never-before-explored territories of vulnerability and conflict. The narrative delves deeply into themes of loss, identity, and the human need for connection, portraying the complications of relationships against the backdrop of the bustling and enigmatic city of Paris. The emotional and psychological tension escalates, leaving the characters to confront the realities they've been trying to escape.