In the luxurious apartment of Mrs. Matilde, Giulia and Andrea, twins with complex personalities and a troubled past, spend their days as servants. However, when the lady of the house is away, the two engage in a unique role-playing game: Giulia assumes the identity of the mistress, while Andrea plays her sister. This game, with its preparations and latent tensions, brings out jealousies and secrets that threaten the precarious balance between the two.