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Animated drama

Children of the Sea (2020): Cast, Ratings & Box Office

Children of the Sea (2020) movie poster

Children of the Sea is a 2020 animated drama directed by Ayumu Watanabe, starring Hiiro Ishibashi as Umi, Benjamin Niedens and Mana Ashida. It is partly based on Children of the Sea, Vol. 1 by Daisuke Igarashi. It runs 1 hour 51 minutes and earned $5.2 million worldwide. Critics gave it 62% on Rotten Tomatoes and 74 on Metacritic.

Rotten Tomatoes
62%
worldwide gross
$5.2M
Echo Score
71
Metascore
74
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Children of the Sea (2020) movie poster
Released
Runtime
1h 51m (111 min)
Director
Ayumu Watanabe
Original language
Japanese
Studio
GKIDS
After the credits
No No extra scene
The story

What Is Children of the Sea About?

The premise of Children of the Sea without spoilers, adapted from Children of the Sea, Vol. 1 by Daisuke Igarashi.

Raised by dugongs, the mysterious brothers Umi and Sora possess a profound connection to the ocean. When strange occurrences begin to silence the world's oceans, a young girl named Ruka is drawn to them. Working at an aquarium with her father, Ruka finds herself entangled in a quest to uncover the secrets behind the oceanic disturbances and the brothers' unique bond with the sea. A journey of wonder, mystery, and adventure unfolds as she seeks answers to the world's deepening enigma.

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Cast & crew

Children of the Sea Cast & Characters

Hiiro Ishibashi leads the cast as Umi, with Benjamin Niedens as Sora and Mana Ashida as Azumi Ruka. Directed by Ayumu Watanabe; 17 actors are credited in all.

From the director

More from Ayumu Watanabe

More films directed by Ayumu Watanabe, best-rated first: Fortune Favors Lady Nikuko, Children of the Sea, Space Brothers: Number Zero and The Big First-Grader and the Small Second-Grader.

Full filmography
Ratings

Children of the Sea Reviews & Ratings

Critics gave Children of the Sea 62% on Rotten Tomatoes and 74 on Metacritic. Our Echo Score gives it 71/100, strongest in art & craft (92) and weakest in story & flow (35).

71 /100

Children of the Sea Echo Score Breakdown

Children of the Sea offers a visually immersive journey while struggling with narrative clarity. Critics and users alike celebrate its stunning animation, cohesive audiovisual design, and thematic ambition exploring human-nature connections. However, the nonlinear pacing and enigmatic plot garnered frequent remarks about confusion and lack of cohesion, with some praising its surreal originality and others finding it frustrating. Despite these divisions, the film delivers an atmospheric experience that rewards viewers open to ambiguity.

Our own 0–100 rating, built from five aspects: art, character, story, the sensory experience and how well a film rewatches.

  • Art & Craft 92

    In terms of art and craft, the film’s visual execution stands out as its primary asset. Reviews consistently praise the detailed hand-drawn-CGI animation, from vibrant color palettes to fluid motion. Critics note the sweeping cinematography of skies and oceans, and users highlight the textured production design. The direction balances whimsy and technical precision to create an immersive canvas. Overall, the animation’s artistry is the film’s most compelling element.

  • Character & Emotion 70

    When it comes to character and emotion, responses are divided. Some reviews highlight a poignant sense of human and more-than-human connection, noting occasional heartwarming moments and thematic resonance. Others find the romantic undertones awkward and the emotional arcs underdeveloped amid the film’s abstraction. While the central figures evoke curiosity, their motivations remain elusive at times. Overall, the character dimension achieves intermittent resonance but never fully coalesces.

  • Story & Flow 35

    In terms of story and flow, the film’s nonlinear structure and measured pacing received mixed reactions. Critics and users describe the plot as enigmatic, with fragmented sequences that challenge narrative coherence and leave thematic threads unresolved. While some appreciate the surreal originality, many find the progression slow and the storyline difficult to follow. Ultimately, the film’s narrative ambition yields a thought-provoking experience for some but a confusing one for others.

  • Sensory Experience 85

    When considering sensory experience, the film’s audiovisual design stands out for its immersive qualities. Multiple reviews commend the evocative score and detailed sound design, which complement the striking visual style and cohesive color palette. Users and critics both cite the synergy between music and imagery as instrumental in creating an atmospheric journey. Overall, the film delivers a compelling sensory tapestry that enhances its thematic exploration of nature and wonder.

  • Rewatch Factor 75

    In terms of rewatch value, the film’s intricate imagery and thematic depth encourage further viewings for attentive audiences. Some viewers report discovering new symbolic details and emotional nuances on subsequent watches, while others cite the ambiguous narrative as a barrier to repeated enjoyment. The enchanting visuals and environmental motifs may reward engagement, but the unresolved storyline can diminish the impulse to return. Overall, the rewatch appeal is present yet selective.

Box office

Children of the Sea Box Office

Children of the Sea grossed $5.2 million worldwide. $81,237 came from the US and Canada and $5.1 million (98%) from the rest of the world.

2020 box office

Worldwide gross

$5.2M

US & Canada
$81.2K
International
$5.1M
US & Canada 2% Rest of the world 98%
Videos

Children of the Sea Trailers & Videos

3 videos: 2 trailers and 1 clip.

Children of the Sea – Trailer – SFF 19
  • Trailer CHILDREN OF THE SEA [Official US Trailer] - APRIL 20
  • Clip Children of the Sea [Official Clip #1 - GKIDS] - Out now on Blu-ray, DVD & Digital!
Cars

Cars in Children of the Sea

14 cars on screen, including the 1981 Honda City and the 1996 Mitsubishi Fuso Super Great.

All 14 cars
  • 1981 Honda City in Children of the Sea 1981 Honda City Minor role
  • 1996 Mitsubishi Fuso Super Great in Children of the Sea 1996 Mitsubishi Fuso Super Great Minor role
  • 1966 Toyota Publica Truck in Children of the Sea 1966 Toyota Publica Truck Minor role
  • 2001 Fiat Palio in Children of the Sea 2001 Fiat Palio Background role
Details

Children of the Sea Also Known As

19 alternative titles, including “Kaijuu no Kodomo” and “Kaijū no Kodomo”.

Also known as
  • Kaijuu no Kodomo
  • Kaijū no Kodomo
  • Les Enfants de la Mer
  • Los niños del mar
  • 해수의 아이
  • Marine Mammal Children
  • รุกะผจญภัยโลกใต้ทะเล
  • 海兽的孩子
  • 海獣の子供:2019
  • Espíritus del mar
  • Дети моря
  • I figli del mare
+7 more
  • 海兽之子
  • 海獸之子
  • Діти моря
  • Những Đứa Con Của Hải Thú
  • Denizin Çocukları
  • Dzieci morza
  • ילדי הים

Seen Children of the Sea?

FAQ

Children of the Sea FAQ: Cast, Box Office & Runtime

Runtime, release date, director, cast, box office, ratings, the book behind it and post-credit scenes of Children of the Sea, each answered in a sentence.

How long is Children of the Sea?

Children of the Sea runs 1 hour 51 minutes (111 minutes).

When was Children of the Sea released?

Children of the Sea was released on September 1, 2020.

Who directed Children of the Sea?

Children of the Sea was directed by Ayumu Watanabe.

More films by Ayumu Watanabe

Who is in the cast of Children of the Sea?

Children of the Sea stars Hiiro Ishibashi as Umi, Benjamin Niedens as Sora and Mana Ashida as Azumi Ruka, among 17 credited actors.

How much did Children of the Sea make at the box office?

Children of the Sea grossed $5.2 million worldwide ($81,237 domestic, $5.1 million international).

How is Children of the Sea rated?

Children of the Sea has 62% on Rotten Tomatoes, 74 on Metacritic, 71% on TMDB and 3.7/5 on Letterboxd.

Is Children of the Sea based on a book?

Yes. Children of the Sea is partly adapted from Children of the Sea, Vol. 1 by Daisuke Igarashi.

Does Children of the Sea have a post-credit scene?

No. Children of the Sea has no extra scene during or after the credits.

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