The year is 2022. Ushio Okazaki is twenty-two, and the world outside the town is buried under endless snow. A mysterious light keeps appearing in the city — she cannot stop seeing it. Her search for its meaning leads through Kotomi's Superstring theory and Yukine's stories of the townspeople, and toward the edge of a world that is quietly ending. The journey has no obvious destination. At its end, she sees something.