Chiikawa the Movie: why a cute little manga became 2026’s biggest hit in Japan
I have read Chiikawa on X, chapter by chapter, as it came out. So when the movie became a phenomenon, my honest reaction was a shrug — a very Usagi “hmm, okay.” I am not a Chiikawa fan in the collecting sense. But characters like these live somewhere in everyone’s daily life in Japan, and I went to see it anyway when a friend invited me.
Chiikawa the Movie: The Secret of the Mermaid Island (opened July 24, 2026, 99 minutes) adapts the manga’s Siren arc. It looks like a kids’ film, but it is darker than the poster suggests, and that gap is a big part of why adults are talking about it. By day 59 it had passed ¥15.84 billion and about 10.86 million admissions, the biggest Japanese release of 2026 so far. Spoiler-light notes below.
Why it took off
The manga is built on a clever bait-and-switch: tiny, round, harmless creatures in a world that is not harmless at all. People knew the characters as cute. The movie asks adults to look at the other half. In the Siren story, there is a killing, a grief that never resolves, and islanders who did something terrible to survive. Reviews have called out revenge, guilt and an unsettling idea of eternal life, and some viewers describe it as closer to horror than a family film.
That is my reading of the hit, and I think the film’s strength is that it never makes the conflict simple. There is no clean villain. Both sides have a reason, and the story does not hand you a verdict. Some readers in Japan also see the series as a quiet picture of precarious lives, with characters scraping by doing odd jobs. I would not call that the official meaning, but it is a lens many people bring, and anime is often the easiest way a wide audience takes in uncomfortable ideas.
My own take, after seeing it
I knew the manga, so for me it was mainly “oh, this is how it moves.” The scenes were familiar; the experience of sitting in a full cinema watching them was the new part. If you have never read it, I think the surprise lands harder. You expect sweet, and you leave quiet.
Do not bring small children unless you have thought it through. Also check the cinema listing for subtitles: I could not confirm English subtitles for the Japanese run. It has been released in Taiwan and Hong Kong with Mandarin and Cantonese dubs. Some screenings use 4DX and cheering-screening formats.
Quick facts
| The movie | |
|---|---|
| Title | 映画ちいかわ 人魚の島のひみつ / The Secret of the Mermaid Island |
| Opened | July 24, 2026 (Japan) |
| Director | Kei Oikawa; original work and script by Nagano |
| Runtime | 99 minutes |
| Based on | The manga’s Siren arc |
| Box office | ¥15.84 billion by day 59; about 10.86 million admissions |
Common questions
What is the Chiikawa movie called?
In English it is Chiikawa the Movie: The Secret of the Mermaid Island (映画ちいかわ 人魚の島のひみつ). It opened in Japan on July 24, 2026, directed by Kei Oikawa, with the original creator Nagano writing the script.
Is the Chiikawa movie for kids?
It looks like a children’s film, but the story deals with revenge, guilt and a killing, and some viewers have described it as closer to horror than a family movie. Think twice before taking very young children.
Do I need to know the manga first?
No. The film adapts the manga’s Siren arc, and it stands on its own. If you know the manga you will mostly be watching familiar scenes move; if you do not, expect the tone to surprise you.
Is there an English-subtitled version?
I could not confirm English subtitles for the Japanese run. The film has been released in Taiwan and Hong Kong with Mandarin and Cantonese dubs. Check the cinema’s listing or ask at the ticket desk before you book.
How successful is it?
Very. As of day 59 it had passed ¥15.84 billion at the box office with about 10.86 million admissions, making it the top-grossing Japanese release of 2026 so far.