As young lovers, Mary and Phil swim out to a buoy in the Irish Sea. Halfway back to the beach, Mary gets cramp and almost drowns. Phil gives her the kiss of life. He saved her life that night. Years later, he develops Parkinson’s disease. Phil starts to stoop and stumble and shuffle his way through each agonizing day. His devoted wife and her family try to adjust to Phil’s frustration and obvious pain. But how much physical pain can a man endure? How much mental stress can a woman tolerate? As he deteriorates, he begs Mary to take him back to the beach of their youth, to head out towards their buoy again, to now save him from his pain.

One night he sneaks out of their cottage and manages to find his way down to the water’s edge. Mary wakes, and goes after him. They walk into the sea and, under the waning moon, head toward the buoy. The ultimate test of their love confronts them: the decision between life and death.