Pietro is a refined 70-year-old retired literature professor who leads a solitary life. The many plants on his terrace are his sole concern, especially the lemon tree, even though it has not been bearing fruits since his wife’s death. Eleonora, 40, has recently moved with her husband Luca into the apartment facing Antonio’s. On a hot summer night, when Luca is away, Eleonora and Pietro meet while they water their plants. It is a magical, seductive encounter that, night after night, will turn into a silent appointment and bring them ever closer.