Parker Gaits is a successful and wealthy businessman who, along with his wife Catherine, plan to purchase a luxury yacht just off shore of the mainland from Peter Thornton, a dashing boat broker. Feeling neglected by her constantly preoccupied husband, Catherine accepts Peter's dinner invitation and gives in to his seduction by spending the night with him aboard his sailboat. But when Peter's continued obsession drives her to the brink of madness she must choose to defend her marriage with the ultimate test of courage and loyalty.