How Long Is the Chiikawa Movie and When Was It Released? Basic Information Summary

The runtime is 99 minutes; released on July 24, 2026

The movie Chiikawa: The Secret of Mermaid Island has a runtime of 99 minutes and was released on July 24, 2026. As of August 18, 2026, it is already showing in theaters. 99 minutes converts to 1 hour and 39 minutes, so when planning around your screening, it helps to factor in this length plus the theater's guidance times before and after the show.

Kei Oikawa directs, original author Nagano writes the screenplay, and Toho distributes the film. The corresponding source material is the Island Arc (Siren Arc) collected in tankobon Volume 8. The English title, The Secret of Mermaid Island, clearly signals the connection to the original through "Mermaid Island," which also appears in the Japanese title. Looking at the original posts depicting the departure for the island, you can immediately grasp the starting point of the journey that became the film's subject matter.

The runtime is 99 minutes, and the film was released on July 24, 2026.

Chiikawa: The Secret of Mermaid Island — Quick Basic Information Table

The film is a 99-minute feature, and its corresponding source material is the Island Arc (Siren Arc) collected in Volume 8. The Island Arc is also sometimes called the "Siren Arc" or "Mermaid Arc," but all of these refer to the same Island Arc in Volume 8. A recruitment notice promising a hundredfold reward and free meals drives the long island story.

Laying out the basic information shows how the original author handled the screenplay and how the film approaches the Island Arc as a 99-minute feature. When you want to check the runtime, staff, distributor, and source material range all at once, the table below is the quickest way. You can avoid confusion by viewing the numbers, like the release date and runtime, separately from who directed and who wrote the screenplay.

Directed by Kei Oikawa, written by Nagano, distributed by Toho

The director is Kei Oikawa, and the screenwriter is Nagano. Nagano, the original author, handled the screenplay, while the director is a different person. Even when introducing the film briefly, writing the director and screenwriter separately lets you convey their roles accurately.

The distributor is Toho. Like the release date and runtime, this is a piece of basic film information—not an indication of the company running the theater. Its role differs from the day-to-day notices about which theater shows the film at what time. Keeping fixed film information separate from changing screening schedules helps you avoid mistaking an old timetable for current plans.

On the original island, the arriving party is greeted with flower garlands, waist ornaments, and island-exclusive foods. Because the story begins with this cheerful welcome, the quality of a "feature-length journey to a distant place"—something staff credits alone can't show—comes through early on. The introduction places the everyday joy of eating side by side with the tension of arriving in an unfamiliar land.

Voice Cast List for the 6 Main Characters

The confirmed main cast includes Haruka Aoki as Chiikawa, Masato Tanaka as Hachiware, Ari Ozawa as Usagi, Yuka Iguchi as Momonga, Yuma Uchida as Rakko, and Minori Suzuki as Siren. Beyond the three heading to the island, the voice actors for Momonga, Rakko, and Siren—who greatly drives the original Island Arc—have all been confirmed.

Chiikawa, Hachiware, and Usagi are the central three who learn of a recruitment notice promising a hundredfold reward and free meals, and cross to the island on a bird-shaped ship. Momonga and Rakko are also part of the original Island Arc cast. With familiar faces gathering on a distant island, the excitement of travel and the tension of a job stand side by side at the same starting point.

The Siren is a great presence that appears at the original story's waterside along with the mermaids. When it shows itself before the three who first heard the mermaids' song, the previously calm boat scene suddenly turns urgent. Minori Suzuki plays this Siren. Note that the mermaids themselves and the Siren are separate characters, so be careful not to mix up their names.

The original Island Arc also features characters beyond the six listed in the table, such as Shimajiro and the mermaids. Their roles and order of appearance in the original can be confirmed from the post cards arranged in publication order on the Island Arc page.

The OP Theme Song Is Sung by Hachiware, with Lyrics by Nagano

The opening theme song is sung by Hachiware, voiced by Masato Tanaka. The lyrics are by Nagano. The voice actor and the singer for Hachiware are the same person, and both the screenplay and the lyrics were handled by original author Nagano. Since the names appear across both the staff credits and the voice cast list, viewing them by role makes the relationships clear.

The theme song is sung by Hachiware (CV: Masato Tanaka), with lyrics by Nagano.

In the original Island Arc, song also serves as a marker connecting characters to the mermaids and the Siren. The scene where a mermaid sings about island food on the cave's water surface, and Chiikawa and friends take it as a cooking song, is a bright exchange from a point when the heart of the situation is still unseen. While keeping it separate from the details of the theme song, paying attention to song as an element symbolizing the Island Arc broadens your doorway into the original.

IMAX Mentioned; Check Theaters and Tickets via Official Information

Screening formats and theaters vary by viewing date, so please check the official movie website and the theater's booking page.

For tickets and theater information, check the latest announcements on the official movie website. Even though the release date is fixed, theaters and showtimes won't necessarily continue in the same pattern. Especially if you want to choose between the regular and IMAX versions, confirming the screening format—not just the title—on the booking page prevents mix-ups. This is the one category of information you should check based on the date you plan to see the film.

In the original, the atmosphere shifts from the island's joyful welcome to a search after news arrives that residents have been disappearing one after another. The waterside, the caves, and the island settlement are settings you can confirm on the original manga side. For the film's specific depictions, please check official information or the movie itself.

The Source Material Is the Volume 8 Island Arc (Siren Arc / Mermaid Arc)

The film's source material range is the Island Arc collected in tankobon Volume 8. On the original's official X account, it ran as a serial across 130 posts from March 14 to November 26, 2023. It expands in stages—from the recruitment notice, to the sea voyage, to the island welcome, to the encounter with the mermaids and the Siren, to the search for residents—making it well suited for anyone wanting to read a full feature-length story in one go.

Along the way, Chiikawa, separated from the others, finds a shell-soup shop and meets Shimajiro. Shimajiro not only recommends food but is someone who heads to the waterside following clues about the others' whereabouts. Like the mermaids and the Siren, he is someone Chiikawa meets for the first time on the island, but even without knowing the story's ending, you can grasp his position as someone extending a hand to Chiikawa in trouble.

Furthermore, the islanders and the traveling party begin making spicy curry as a means to stop the Siren. Kurimanju serves as head chef, Shisa as taste-tester, and Chiikawa and Hachiware gather ingredients. The way an island journey that began with food connects to a collaborative project using food is an Island Arc kind of fun. Even without revealing the ending, the growing cast of companions comes through clearly.

To follow the original posts in publication order, start from the Island Arc page; to read it in collected book form, Volume 8's page is your entry point. After grasping the film's basic information, moving on to the original lets you confirm at your own pace why the characters came to the island and the buildup to facing the Siren.