Nagano’s beloved pop-culture phenomenon has achieved another monumental milestone. The franchise's inaugural theatrical feature, Chiikawa Movie: Secret of Mermaid Island, has officially crossed the 10 billion yen threshold at the Japanese box office. Released on July 24, the film reached this historic milestone in just 30 days, as confirmed by the official production committee.
The Siren Arc Takes Center Stage
Adapted from the widely celebrated "Siren Arc" of the original web manga, the film brings a darker, high-stakes narrative to the normally lighthearted world of Chiikawa, Hachiware, and Usagi. Directing duties were handled by Kei Oikawa at studio CygamesPictures, drawing praise for seamless character animation and kinetic action sequences under the direct supervision of creator Nagano.
Historic Box Office Pace
The film opened to record numbers, drawing over 1.5 million viewers and generating 2.24 billion yen during its initial three-day opening weekend. With this trajectory, it becomes the fourth animated film in Japan to surpass 10 billion yen in 2026, joining major blockbusters such as Zootopia 2 and Detective Conan: Highway's Fallen Angel.
