Edges a psychological thriller centered around two women: Rebecca, the beautiful sophisticated wife of Henry; and Katelyn, the sweet fragile mistress who is madly in love with him. After suffering a devasting miscarriage, Rebecca secretly discovers her husband of 20 years has been unfaithful again. Only this time, he intends to leave her. Rebecca refuses to accept this information and confronts her husband's mistress in an attempt to destroy this new relationship and keep her husband. This confrontation is met with unexpected results.