Based on the plot of an award-winning Crayon Shin-chan animated movie from 2002, a boy named Shinichi time-travels and meets a feared general named Ijiri Matabei. Ijiri is in love with Princess Ren, who subsequently rejects an arranged marriage to Okura Itakatora, a powerful daimyo of northern Kanto. Enraged by the rejection, Okura sends a large army to Ijiri's smaller state, and it's up to Shinichi to change their destiny.