Chiikawa the Movie: The Secret of the Mermaid Island Opens at No. 1 in Japan With $13.7 Million Debut

Chiikawa the Movie: The Secret of the Mermaid Island has made an impressive debut at the Japanese box office, opening at No. 1 and delivering one of the strongest anime launches of the year. The film, based on Nagano’s popular Chiikawa web manga, premiered on July 24 in 447 theaters, including 65 IMAX locations, and quickly established itself as the weekend’s biggest release.

According to Kogyo Tsushinsha, with additional box office figures reported by Oricon News and Animate Times, the film earned 2.24 billion yen ($13.68 million) from 1.51 million admissions during its first three days.

Chiikawa sets a new opening-day milestone

The movie adapted the fan-favorite Siren Arc from the original manga and immediately attracted audiences across Japan. According to Oricon News, it collected 990 million yen ($6.05 million) on its opening day alone, surpassing the 960 million yen opening-day record previously held by Detective Conan: The Million-dollar Pentagram.

Its three-day performance now ranks as the second-largest opening weekend for a Japanese anime film in 2026, trailing only Detective Conan: Fallen Angel of the Highway, which launched with 3.35 billion yen earlier this year.

Official key visual for Chiikawa the Movie The Secret of the Mermaid Island, which debuted at No. 1 at the Japanese box office. (Image via Doga Kobo)

Audience reception has also been strong. Review platform Filmarks ranked the film first in its opening-day satisfaction rankings, where it received an average score of 4.17 out of 5 based on more than 7,300 user reviews.

The success of Chiikawa the Movie pushed Kingdom: Tamashii no Kessen (The Decisive Battle of Souls) down to third place during its second weekend. The live-action adaptation earned 734 million yen ($4.48 million) from 449,600 admissions, representing a 53.7% decline from its opening weekend.

Despite the drop, the fifth Kingdom film has accumulated 3.3 billion yen ($20.15 million) after two weekends, reaching roughly 91.7% of the pace set by its predecessor, Kingdom: Return of the Great General, over the same period.

Elsewhere, Toy Story 5 remained in second place, while several newcomers—including Kamen Rider Zeztz & Super Space Sheriff Gavan Infinity: W Hero Summer Movie 2026 and PAW Patrol: The Dino Movie—also entered the Top 10. Meanwhile, Detective Conan: Fallen Angel of the Highway exited the Top 10 after 16 weekends but has amassed 13.65 billion yen ($83.36 million), making it the 27th highest-grossing film in Japanese box office history.