During World War II, the sailor Anatoly and his captain, Tikhon, are captured by the Germans when they board their barge and tugboat, which is carrying a shipment of coal. The Nazi officer leading the raid offers Anatoly – who is terrified of dying – the choice to be shot or to shoot Tikhon and stay alive, which Anatoly takes; he shoots, and Tikhon falls overboard. The Nazis blow up the ship but Anatoly is found by Russian Orthodox monks on the shore the next morning. He survives and becomes a stoker at the monastery but is perpetually overcome with guilt.
Thirty years pass. Anatoly now has the gifts of prophecy and healing. But the other monks do not really understand him. People come to see Anatoly for cures and guidance, but even now, he remains in a perpetual state of repentance. He often gets in a boat and goes to an uninhabited island where he prays for mercy and forgiveness.
Many years pass, and an admiral of the North Fleet arrives at the monastery. He brings his daughter who is possessed by a demon, but Anatoly exorcises it. The admiral turns out to be Tikhon. It is revealed that Anatoly only wounded him in the arm. Tikhon forgives Anatoly.
Anatoly announces his death by Wednesday; the monks provide a coffin. Dressed in a white garment such as Jesus wore or as an Orthodox baptismal garment, he lies in the coffin, wearing a crucifix. Monks, one carrying a large cross representing the risen Christ, are seen rowing the coffin away from the island.