In everyday life, Joan is self-controlled and determined to be in charge of every detail around her. In the presence of Daniel, however, she is a slave to his every desire, so when he suggests that she meet the beautiful Isabelle she cannot refuse. While she struggles to control her jealousy, however, she is also intrigued by this mysterious woman, and when both of them dominate her completely she begins to understand at last why Daniel has chosen to be her master, and why Isabelle is herself a slave to other passions.