Chiikawa the Movie: The Secret of the Mermaid Island , the first anime feature film inspired by Nagano's web manga series Chiikawa , opened in 447 theaters across Japan (382 standard theaters + 65 IMAX theaters) on July 24 and debuted at the top of the weekend box office rankings, according to Kogyo Tsushinsha . The film adapts the Siren Arc , a particularly popular story arc from the original manga series. Oricon News reported that Chiikawa the Movie earned 990 million yen (6.05 million USD) on its opening day, surpassing the opening-day gross of 960 million yen (5.86 million USD) set by Detective Conan: The Million-dollar Pentagram in 2024, the highest-grossing film in the Detective Conan anime franchise. Chiikawa 's three-day opening gross reached 2,240,333,500 yen (13.68 million USD) with 1,508,538 admissions, according to Animate Times . This marks the second-best opening for a Japanese anime film released this year, following Detective Conan: Fallen Angel of Highway 's 3.35 billion yen (20.46 million USD). Chiikawa the Movie also ranked first in Filmarks' first-day satisfaction ranking with an average score of 4.17/5.0 based on 7,381 reviews.