On Tamagotchi Planet, Mametchi has just finished his new creation. But on its first trial run, Kuchipatchi manages to throw the machine's aim off course, which results in a child from Earth, Tampopo, being transported to the Tamagotchi Planet.

Mametchi and his friends must save Tamagotchi world from a book that is beginning to destroy reality, entitled "The World's Happiest Story".