Lucky is he who knows the causes of things...

The action takes place in post-World War II Estonia. An old man lives alone on a deserted island which the Soviet fighter planes use for nighttime target practicing. A young neglected boy, who has become mute, is banished from the mainland and sent to the island to keep the old man company. Both are haunted by memories, the boy about his mother and the old man about the years before World War I he spent as a young missionary in Africa