InuYasha the Movie 4: Fire on the Mystic Island

InuYasha the Movie 4: Fire on the Mystic Island concludes the theatrical InuYasha series with a storyline centered on Horai Island — a hidden land that appears only once every fifty years and is populated by children with four-soul stones, trapped serving the powerful entity known as the Shitōshin (Four War Gods). InuYasha has a personal connection to the island from his past, and when the island reappears, he must face both the War Gods and his own history there. The film features one of the most prominent Sesshomaru roles in the theatrical series outside of his sibling-focused film.

Fire on the Mystic Island is generally considered the weakest of the four InuYasha films, with a villain group (the Shitōshin) that lacks the depth of Kaguya or the lore significance of Sō'unga. The children-in-peril premise is emotionally familiar, and the resolution feels somewhat rushed within the film's 87-minute runtime. However, the animation quality is strong and the action sequences are well-executed. For fans who want to complete the full InuYasha theatrical experience, it provides a reasonable, if not spectacular, conclusion to the series. Non-canonical throughout, with no impact on the main storyline.