One day, while on a school field trip, child prodigy Sorata Suzuhara hears a mysterious song, wanders off from his class, and blacks out. When he comes to, he finds himself in an unfamiliar place, and soon encounters a girl who informs him that he’s in Taisho era Japan! She leads him to a ship she’s been waiting for in order to help him get home, but when it appears, it is not a wooden sailing ship, but a round aircraft that flies using technology beyond Sorata’s imagination.
Even stranger, he discovers twelve others – three young women and nine young men – are all supposedly espers with special powers, on some kind of journey at the behest of a multinational entity known only as The World. What is the purpose of their journey? What is their destination, and what is The World? Before Sorata can even begin to take stock of his situation, the ship is attacked, and the mystery surrounding the ship only deepens. Delve into the story of the ship and its occupants through the point of view of each of the three girls, and unravel the mysteries trapped within.