The Chiikawa movie: release, box office, and what to read before or after

Read the original story first (or after): the Siren Arc

The movie adapts the Siren Arc, posted on Nagano’s X account from Mar 15, 2023 to Nov 26, 2023. Chiifan lines up all 96 posts in order as X embeds, so you can read the source from the very first post.

• The page is in Japanese, but you only need to scroll: the X posts are shown in order from top to bottom, 10 per page. Use the “next page” button at the bottom to continue.
• The comic has little text and much of it is told through expressions, so you can follow a lot of it without reading Japanese.
• 96 is the number of posts we collected, not an official episode count.

• Siren Arc from post 1(Japanese)
• Siren Arc guide (which volume, no spoilers)

The movie in South Korea

It opened in South Korea on Sep 30, 2026, with the subtitled and Korean-dubbed versions released the same day. Korean media reported that admissions passed 1 million on Oct 9, 2026, the 10th day of release.

• Korean title: 『극장판 치이카와: 인어 섬의 비밀』 (as announced by Chiikawa Shop Korea). The Korean running time is listed as 98 minutes (CINE21).
• On opening day (Sept 30) it was No. 1 for the day in Korea, with 122,293 admissions (KOBIS daily figures).
• As of Oct 9, Korean media reported it was the 3rd-biggest animated film released in Korea this year. It was also reported as the first Japanese animated film released there this year to pass 1 million.
• In the Korean dub, Hachiware is called “Gareuma” (가르마) and Usagi “Tokki” (토끼). The lead voices are Lee Ju-eun (Chiikawa), Son Jeong-min (Hachiware) and Kwon Da-ye (Usagi).
• CGV, Lotte Cinema, Megabox and CineQ are giving out weekly bonuses (the 2nd-week bonus from Oct 7; no end date announced). Check each chain’s app for what is left.

• Our Japanese article on the Korea release(Japanese)

The movie in Japan

It opened in Japan on Jul 24, 2026. As of Oct 6, 2026 it was still showing nationwide; end dates differ by theater. Toho announced over ¥17.2 billion and 11.78 million admissions in its first 75 days.

• Formats: standard, IMAX, and 4DX (from Sept 5). Running time 99 minutes, rated G.
• Japanese theaters hand out a different bonus gift every few weeks; the 6th, a mini charm figure, started on Oct 10, 2026, while supplies last.

• Official movie site(Japanese)
• Our Japanese movie summary(Japanese)

Before or after the movie: what to read (no spoilers)

You can enjoy the movie without knowing the comic. Either order works; here is a simple way to choose.

• Before the movie: meet the main trio (Chiikawa, Hachiware, Usagi) on our character page. You don’t need to read the Siren Arc first.
• After the movie: read the Siren Arc from post 1. It ran for about eight months as 96 posts, so you can follow the story in the order and at the pace Nagano first posted it. In print, it is Vol. 8 of the Japanese books.
• Want a short taste of the comic instead? Try the Muchauman Arc (10 posts). Other long arcs are listed on our manga guide.

• Chiikawa characters
• All story arcs
• Muchauman Arc

Frequently asked questions