The Joker five-star system is under Emperor Amaterasu. Mecha pilot Ladios must save his co-pilot, Fatima-class female android Lachesis, from one of many warlords, who oppose Amaterasu.

While performing in a student film, Ataru cuts down Tarozakura, a large, ancient cherry tree. Strange things begin to happen all across Tomobiki: a mountain appears out of nowhere, spring changes to winter, and Lum loses her powers, while those around her act as if she doesn't exist.

A curse placed on Lum as an infant manifests itself in the present day, causing her to be taken to another dimension. Lum's husband, Ataru Moroboshi is turned into a hippo, and attempts to find Lum with the help of her friends.