The cultural phenomenon surrounding Nagano’s Chiikawa shows zero signs of slowing down. Eiga Chiikawa: Ningyo no Shima no Himitsu (The Secret of Mermaid Island), the first feature-length theatrical adaptation of the beloved manga, successfully defended its reigning position at the top of the Japanese box office during its eighth weekend. Over the three-day span from Friday to Sunday, the Cygames Pictures production pulled in an impressive 271,000 ticket sales, translating to roughly 427,295,700 yen (approximately $2.75 million USD).
These figures push the film's cumulative performance to astronomical heights. With over 10.09 million tickets sold to date, the feature has generated a staggering 14,666,866,500 yen (about $94.61 million USD). Having previously overtaken Detective Conan: Fallen Angel of the Highway, the project proudly stands as the highest-earning theatrical release in Japan for the current year, cementing itself comfortably at 23rd place on the country's all-time box office charts.
Box Office Rivalries and Milestone Releases
As the summer blockbuster season matures, other high-profile adaptations and sequels continue their theatrical runs alongside Chiikawa. SHAFT’s Puella Magi Madoka Magica The Movie: Walpurgisnacht: Rising adjusted to fourth place in its third weekend, accumulating 1,838,112,960 yen (approx. $11.85 million USD) total following its IMAX expansion. Meanwhile, Kyoto Animation’s grand finale Sound! Euphonium, The Final Movie Part 2 debuted strongly in the top tier following its mid-September rollout, maintaining the prestige of the studio's musical drama heritage.
The Mermaid Island arc, originally published by Nagano on X between March and November 2023, brought a uniquely unsettling yet charming narrative journey to the big screen. Directed by Kei Oikawa under Nagano's direct supervision and script oversight, the film balances whimsical creature comforts with genuine narrative tension—a formula that continues to resonate with millions of theatergoers across generations.
