Snowball Earth is a high-octane science fiction and mecha manga written and illustrated by Yuhiro Totsuno. It is widely praised for its cinematic action, unique monster designs, and a story that combines the loneliness of space with the gritty survival of a frozen apocalypse.

The story follows Tetsuo, a socially anxious boy who only feels comfortable inside his giant combat robot, Yukio. After a ten-year-long battle in deep space to protect Earth from a swarm of alien monsters known as "Galau," Tetsuo finally returns to his home planet. However, instead of a hero's welcome, he finds a world completely encased in ice—a "Snowball Earth"—where humanity is on the brink of extinction and new, terrifying creatures roam the frozen wasteland.