The story of mermaids loving humans continues to stand the test of time, and in STUDIO4°C’s latest animated film, ChaO, takes the familiar concept and injects it with the silliest energy. However, there’s much more beneath the surface once you look past the high-energy antics. Directed by Yasuhiro Aoki and written by Saku Konohana, this animated venture explores the politics of interspecies relations, the conditional nature of capitalism and its impact on the environment, and more broadly, the idea of destined love.
Starting in a more futuristic Shanghai, a young reporter seeking a scoop accidentally runs into the legendary Stephan, the catalyst for the successful promotion of coexistence between mermaids and humans. Getting a chance to set the story straight, Stephan (Ouji Suzuka) dives deep into his memories to reveal the realities of his love story with ChaO (Anna Yamada), a princess from the mermaid kingdom.
Their initial meeting starts with an accidental drowning, where ChaO rescues Stephan. From there, it’s a whirlwind of events as Mr. Sea, Stephan’s boss, proposes they marry, jump-starting a beneficial relationship between his company and the merpeople. To say it is a mismatch would be an understatement; ChaO’s physique and aquatic appearance draw tons of attention wherever they go.
The clash of cultures and physiologies is obvious, and despite ChaO’s affection for Stephan, this love story seems destined for unhappiness. A third-act moment of realization from Stephan rights the ship; however, it doesn’t do as much to rehabilitate him as a worthy husband as one might hope. Still, it does just enough to make the pairing easier to justify, even if it’s just tying together the loose strings of their destined connection.
Chao is too cute for words, and Stephan is kind of trash, which is part of the problem with the love story.

What makes ChaO work is how much director Yasuhiro Aoki and writer Saku Konohana lean into the natural absurdity and silliness that a mermaid/human pairing might have. It opens up a broader nature-versus-civilization debate, as these two aspects clash (and, as seen later in the film, harm both aquatic and human life). Finding a way to meld the two in harmony is the conflict, and in the film’s first half, it is explored by leaning into more comedic beats before switching gears to something more serious.
The film’s world is vibrant, with an incredibly unique art style that plays with proportions to an absurd degree. It can be an adjustment to the eye, with some character designs being more distracting than others. However, when it works, it really works. Characters like Mr. Sea, the titular Chao, and her father, the King of the Sea, have standout character designs, with their comical, ever-changing proportions that only enhance their personalities and emotional states.
All of this culminates in the delightful scene-stealing character that is Chao. Her naivety and earnestness make her initial coupling with Stephan all the more sad. Anna Yamada brings her character to life with charm and exuberance, complementing the adorable yet clumsy antics as she tries to assimilate into the human world. Similarly, Ouji Suzuka leans into Stephan’s awkwardness and exasperation with everyone, yet while Stephan is unlikable, Ouji’s empathetic performance later on softens the saltier edges.
STUDIO4°C deliver a unique spin on a classic fairy tale.

As is the case with any recollection, Stephan’s memory of events is unevenly paced, with his forced betrothal and marriage to Chao and how that all came to be taking up a good portion of the film’s time. This leaves the film’s final third feeling like a rush to reconciliation, with Stephan’s coming to terms with his feelings and connection to Chao needing more time to simmer before the climactic ending of his tale. More moments to flesh out his feelings would have done wonders, even if it extended the runtime.
Even so, as a retelling of a classic mermaid love story, STUDIO4°C offers an incredibly unique spin on a familiar archetypal fairy tale. These are not the kind of mermaids that immediately come to mind, amplifying the obvious differences in this cross-species relationship.
Director Yasuhiro Aoki and writer Saku Konohana never lose sight of the natural comedy that comes from such a plot, and with the help of the adorable scene-stealing sensation, Chao, you can’t help but keep watching.
ChaO is now playing in theaters nationwide.
ChaO
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Rating - 7/107/10
TL;DR
As a retelling of a classic mermaid love story, STUDIO4°C offers an incredibly unique spin on a familiar archetypal fairy tale.






