A story that appears at first glance to be a detective story, or a novel about a marital relationship that is torn apart, or an exploration of buried secrets from the mysteries of World War II. The hero is Toru Okada: a young Japanese man looking for his wife's lost cat. However, he soon finds himself on a journey in search of his wife in another hidden world. His search for a cat intersects with his search for a wife, and he encounters a strange group of friends and enemies, each with a story: from the playful girl, to the spiteful politician, to the ex-fighter.