A man named Kim jumps into the dark, quiet waters of the Han River. He wakes up and finds himself lying on strange ground, covered with sand. For a second he thinks he is in heaven, but soon recognizes that he simply drifted to a nameless island. In one of the riverside apartment buildings there's a girl who hasn't ventured out of her room for years. With her dishevelled hair and in the same old clothes she's worn for years, she looks just like a castaway. Then one day she catches sight of a man living alone on an island through her binoculars. Day after day, his lonely but seemingly contented life triggers her curiosity and compels her to step out of her room after so many years. Kim's extraordinary life becomes the inspiration for change in this girl's lonely, detached life.