On a cruiseship bound for Buenos Aires, a wealthy passenger challenges the world chess champion to a match. He accepts with a sneer. He will beat anyone, he says. But only if the stakes are high. Soon, the chess board is surrounded. At first, the challenger crumbles before the mind of the master. But then, a soft-spoken voice from the crowd begins to whisper nervous suggestions. Perfect moves, brilliant predictions. The speaker has not played a game for more than twenty years, he says. He is wholly unknown. But somehow, he is also entirely formidable ...