Catherine (Julianne Moore), a successful doctor, suspects her husband David (Liam Neeson), a handsome music professor, is cheating on her. To lay her suspicions and fears to rest, she hires an irresistible young woman, Chloe (Amanda Seyfried), to test David’s fidelity. Chloe’s torrid tales of her encounters with David lead Catherine on a journey of sexual and sensual re-discovery. But by opening the door to temptation, she puts her family in great danger.