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Fantasy animated film

Children of the Sea (2019): Cast, Ratings & Box Office

Children of the Sea (2019) movie poster

Children of the Sea is a 2019 fantasy animated film directed by Ayumu Watanabe, starring Mana Ashida as Ruka Azumi (voice), Hiiro Ishibashi and Seishu Uragami. It runs 1 hour 51 minutes and earned $5.2 million worldwide. Its Echo Score is 60/100.

worldwide gross
$5.2M
Echo Score
60
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Children of the Sea (2019) movie poster
Released
Runtime
1h 51m (111 min)
Director
Ayumu Watanabe
Original language
Japanese
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.

A young girl named Ruka, whose parents are separated and whose father works at an aquarium, finds herself drawn to two mysterious boys, Umi and Sora. Raised by dugongs in the sea, the boys are brought to the aquarium, and Ruka discovers she shares a supernatural connection to the ocean like them. Unusual events begin to occur, including the unexpected appearance of marine life and the disappearance of aquarium animals. As Ruka investigates, she and her new friends must uncover the source of their power and the cause of the escalating disturbances in the ocean.

Children of the Sea Themes & Keywords

· 50 tags
  • aquarium
  • fish
  • sea
  • beach
  • friendship
  • boat
  • female protagonist
  • voice over
  • voice over narration
  • seaside
  • young girl
  • handball
+38 more
  • tripped
  • turtle
  • classroom
  • train
  • ice cream
  • thunderstorm
  • heavy rain
  • shark
  • slapped in the face
  • underwater scene
  • cooking
  • night
  • campfire
  • will o' the wisp
  • ball
  • scene after end credits
  • newborn baby
  • newborn
  • baby
  • umbilical cord
  • cutting umbilical cord
  • starfish
  • japanese animation
  • japan
  • sea life
  • montage
  • underwater
  • schoolgirl
  • summer vacation
  • summer
  • seaside town
  • detention
  • bruised knee
  • meteorite
  • humpback whale
  • whale song
  • whale shark
  • rain
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Cast & crew

Children of the Sea Cast & Characters

Mana Ashida leads the cast as Ruka Azumi (voice), with Hiiro Ishibashi as Umi (voice) and Seishu Uragami as Sora (voice). Directed by Ayumu Watanabe; 9 actors are credited in all.

Also Starring in Children of the Sea

· 5 more
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

Our Echo Score gives it 60/100, strongest in art & craft (82) and weakest in story & flow (38).

60 /100

Children of the Sea Echo Score Breakdown

Children of the Sea presents a striking visual feast that is counterbalanced by a fragmented narrative, resulting in a mixed overall impression. Critics and users alike commend the vivid animation, atmospheric water imagery, and evocative soundtrack, describing the film as a visual wonder. Conversely, many point to a disjointed plot, opaque thematic execution, and pacing issues that leave viewers unsettled. The combination of strong sensory craftsmanship with uneven storytelling yields a moderately favorable but cautious recommendation.

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

  • Art & Craft 82

    The film excels in visual craftsmanship, with critics highlighting its vivid animation, stunning water imagery, and meticulous hybrid hand‑drawn CGI. The direction and production design create an immersive oceanic world that many consider poetic. A few reviewers note occasional excess that overwhelms the aesthetic balance. Overall, the artistic execution stands out as a major strength of the movie.

  • Character & Emotion 50

    Character portrayal is uneven, with some viewers finding the romantic subplots and interactions forced or out of character. While the animation captures subtle expressions, the lack of clear development and occasional cringe‑worthy moments reduce emotional resonance. Positive remarks are sparse, focusing on brief moments of nuanced performance. Consequently, character depth and chemistry are perceived as middling.

  • Story & Flow 38

    Narrative coherence is a persistent concern; many critics describe the plot as fragmented, confusing, and lacking closure. The pacing is cited as slow, and thematic ambitions are seen as overwhelming rather than enlightening. A minority appreciate the ambition and philosophical scope, yet the overall consensus points to a story that fails to engage consistently. Storytelling therefore registers as a notable weakness.

  • Sensory Experience 78

    Sensory experience receives strong praise for its breathtaking visuals, atmospheric sound design, and an evocative musical score that complement the oceanic setting. Reviewers emphasize the beauty of the water imagery and the immersive audio landscape. Some note occasional visual overload, but these instances do not diminish the overall sensory impact. The auditory and visual elements together form a compelling highlight of the film.

  • Rewatch Factor 48

    Rewatch potential is mixed; the film’s visual splendor invites repeat viewings, yet narrative opacity and pacing issues deter many from returning. Some users express a desire to revisit the film to unpack its thematic layers, while others find the experience pretentious enough to avoid a second watch. This split perception yields a moderate rewatch factor.

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.

2019 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

2 videos: 2 trailers.

Children of the Sea – Trailer – SFF 19
  • Trailer CHILDREN OF THE SEA [Official US Trailer] - APRIL 20

Seen Children of the Sea?

FAQ

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

Runtime, release date, director, cast, box office, post-credit scenes and language 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 May 19, 2019.

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 Mana Ashida as Ruka Azumi (voice), Hiiro Ishibashi as Umi (voice) and Seishu Uragami as Sora (voice), among 9 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).

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

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

What language is Children of the Sea in?

The original language of Children of the Sea is Japanese.

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