Sophia is deeply hurt when her husband Billy loses interest in her and even turns to porn magazines instead of touching her. To regain her figure and save her marriage, she joins a swimming camp, only to discover that the coach is her husband’s younger brother, Michael. Under Michael’s patient guidance, Sophia’s body becomes increasingly attractive, and a spark of forbidden desire grows between them. Meanwhile, Billy’s mistress, Chloe, sneaks into the camp, films Michael defending Sophia, and persuades Billy to set a trap to frame her for infidelity. Billy forces Michael to seduce Sophia and record their encounter within a week, so that Sophia will be left with nothing in a divorce. With no other choice, Michael reluctantly agrees. Unaware of the scheme, Sophia, believing her husband has had a change of heart and wants to retake their wedding photos, takes the initiative to invite Michael to continue teaching her at home — step by step walking into the trap.
