When the mysterious Shiriri turns his parents into children, Shin-chan must trek across Japan to help return them to adult form.

After accepting an invitation from a mysterious trainer, Ash, Misty and Brock meet Mewtwo, an artificially created Pokémon who wants to do battle.

Follow the friendship between the Nobara family’s pet dog Shiro and a “small dinosaur”. Their connection helps the growth of Shinnosuke and the Kusakabe Defense Squad.