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

Shin-chan is approached by his time-traveling future bride-to-be Tamiko, who asks him to help save his adult self from the ruler of Neo Tokio.

A mysterious virus, nicknamed Medusa, is spreading around Japan, turning its victims into stone. Given the impossibility of finding an immediate cure, the government opts for cryopreserving a select group…