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Doraemon the Movie: Nobita’s New Undersea Devil Rock Castle—do you want to know where you can watch it?

In this article, we’ll explain everything clearly and carefully, from how to see the newest film in theaters (opening on Friday, February 27, 2026) to ways you may be able to watch it for free after release and routes for watching it at a super low price. Based on the buzz around Airi Taira being appointed as the film’s promotional ambassador, let’s check the fastest and most cost-effective way to watch it.

This article prioritizes the latest information organized around the release date and official announcements. First, for those who want to quickly check viewing options, we’ve prepared a search link.

🔗 View Amazon search results for Doraemon the Movie: Nobita’s New Undersea Devil Rock Castle

Where can you watch Doraemon the Movie: Nobita’s New Undersea Devil Rock Castle, kuma?
It opens on February 27, 2026, kuma! The basics are theaters, but after that you can aim for streaming, kuma~.
Watching in theaters is the classic route, kuma, but do you want to watch for free or super cheap, kuma?
Mirukuma will research thoroughly and bring you the best deals, kuma~!

What Is Doraemon the Movie: Nobita’s New Undersea Devil Rock Castle?

Doraemon the Movie: Nobita’s New Undersea Devil Rock Castle is the latest theatrical anime film, set to premiere on Friday, February 27, 2026.
This film is planned as a grand adventure story set on the ocean floor, and it’s also generating buzz because Airi Taira has been appointed as the promotional ambassador ahead of release.
Starting with its theatrical run, this is a highly anticipated title expected to later move to streaming and physical media.

Release Date and Basic Information

The release date has been set for Friday, February 27, 2026.
The genre is science fiction animation, positioned as a major family-friendly release.
Advance tickets at theaters (except for some venues) are scheduled to go on sale starting Friday, December 5, according to the announcement.
Attention is on both the film’s opening box-office performance and what happens with the subsequent digital distribution schedule.

Production Staff and Cast (Main Characters)

This film is being produced as a work that carries on the lineage of the long-running Doraemon series.
In addition to familiar faces like Doraemon, Nobita, Shizuka, Suneo, and Gian, information about guest voice actors is being revealed in stages.
At the time of announcement, the first guest voice actor reveal was already made, including a role as El, a soldier who lives under the sea.
Also, the involvement of Airi Taira as the promotional ambassador further adds to the film’s buzz.

Themes and Positioning of the Film

By using the ocean floor as its setting, the film appears intended to depict universal themes such as curiosity about the unknown, teamwork, and courage.
The “New” in the title suggests a remake or reinterpretation of a past film, aiming to preserve homage to the original while reconstructing it with modern staging and direction.
The unique undersea setting in particular is expected to deliver new approaches in visual and sound design, making it a film that audiences of all ages can enjoy.

What kind of story is Nobita’s New Undersea Devil Rock Castle, kuma~?
Just hearing “a big adventure under the sea” makes me excited, kuma!
Mirukuma wants to see it in theaters ASAP too, kuma, but first we need to secure good seats, kuma~!
Extra-large popcorn is a must, kuma~!

Story Synopsis and Film Information for Doraemon the Movie: Nobita’s New Undersea Devil Rock Castle

The story of Doraemon the Movie: Nobita’s New Undersea Devil Rock Castle is a grand adventure set on an unknown “ocean floor” that no one has ever seen.
In this section, we’ll carefully explain the setting, highlights, and basic release information while avoiding spoilers.

Synopsis (Spoiler-Free Overview)

Nobita and friends encounter a mysterious undersea city said to be close to the depths of the Earth, along with the people and soldiers who live there.
An incident occurring behind the scenes of what seems like a peaceful undersea world draws Doraemon and the others in and escalates into a major adventure.
The story progresses around the spirit of exploration into unknown places and developments that test the bonds between friends.
It has already been announced that the guest character El, a soldier who lives under the sea, will play an important role.
The story is structured for the whole family to enjoy, featuring both kid-friendly excitement and elements that adults can appreciate.

Runtime, Target Audience, and Preview of Highlights

Based on trends in past theatrical Doraemon films, the runtime is expected to be around roughly 100 minutes.
The primary audience is children and families, but it’s also expected to be designed with longtime fans and new viewers in mind.
Key highlights include the visual presentation that takes advantage of the unique undersea setting, as well as the drama that unfolds there.
In addition, the performances of the guest voice cast and the sound/music direction will likely enhance immersion in the film.

Release Schedule (Advance Tickets / Theater Information)

The theatrical release date is set for Friday, February 27, 2026.
Advance tickets are scheduled to go on sale starting Friday, December 5 (excluding some theaters), per the official announcement.
Because theaters and showtimes vary by venue, we recommend checking information from your nearest theater as the release approaches.
Crowds are expected right after release, so if you want good seats, consider advance tickets or an early showing on opening day.

Just the synopsis gets me excited, kuma~!
What kind of character is El, the undersea soldier, kuma? Mirukuma is curious too, kuma~.
Theaters will be crowded, so definitely check advance tickets, kuma.
Let’s grab good seats, kuma~!

Highlights and Key Appeal Points to Know Before Watching

Here are the main highlights and appeal points you’ll want to know before watching Doraemon the Movie: Nobita’s New Undersea Devil Rock Castle.
This film stands out for its large-scale story structure set on the “ocean floor” and for portraying the series’ timeless themes through fresh expression.

Character Highlights

In this film, the teamwork and growth of the main characters—Nobita and Doraemon among them—will be a major pillar.
Especially in the extremely unique environment of the ocean floor, it’s a highlight to see how each character uses their strengths.
The presence of the guest character El, announced as a soldier, is expected as a key figure central to the story.
Themes that have long supported the series—like friendship and courage—are likely to create even deeper emotional impact when combined with the undersea drama.

Technology and Animation Expression

With an undersea setting, visual and sound design ingenuity becomes especially important.
This film is expected to heighten visual immersion through elements like underwater light 표현, fluid motion, and expansive spatial staging.
On the audio side, three-dimensional sound design that leverages underwater quietness and distance perspective will likely support the realism of the world.
It’s also a point of attention how the film balances introducing new CG and direction techniques without compromising the character portrayal fans expect.

Tips for Watching as a Family

Because the film is produced mainly for children and families, there are considerations throughout that suit family viewing.
When watching with small children, it’s a good idea to consider sound volume and seat location.
While theaters deliver stronger emotion through immersion and sound, streaming or rental viewing offers home-friendly conveniences like pausing and switching subtitles.
By talking together as a family about emotional scenes and the film’s messages, the viewing experience can become even more meaningful.

So many highlights, kuma~!
I’m looking forward to Doraemon and friends growing up, and the undersea visuals too, kuma~.
Mirukuma loves great sound, so I want to hear it loud in theaters, kuma!
But relaxing at home with subtitles is hard to pass up too, kuma~!

Subscription Services Likely to Stream Doraemon the Movie: Nobita’s New Undersea Devil Rock Castle Later

This is a predicted list of which video streaming services are likely to carry it after the theatrical release (February 27, 2026).
The table below summarizes the predicted start time (year/month), estimated pricing, and ways to watch for free, based on each service’s past distribution tendencies and typical domestic distribution patterns in Japan.

How to Read the Table and the Basis for the Predictions

These predicted dates are calculated by referencing the theatrical release date (February 27, 2026), typical transition periods for similarly sized theatrical anime titles, and general tendencies of each service’s distribution policies.
Specifically, it’s common that rental streaming and digital sales are prioritized first, then VOD rentals begin about 1–4 months later, and subscription unlimited viewing often follows around 4–10 months later, and these patterns are reflected here.
We also differentiate timing based on each service’s strengths (anime-focused vs. general, exclusivity tendencies, etc.).

It’s hard to decide which service to use, kuma~!
For Mirukuma, if you want to watch early, theaters or TSUTAYA rentals seem good, kuma!
If you want to watch for free, aim for U-NEXT trials or ABEMA campaigns, kuma~!

Frequently Asked Questions About Watching Doraemon the Movie: Nobita’s New Undersea Devil Rock Castle

We answer common questions readers may have before watching—such as the theatrical release date, streaming timing, and how to watch as a family—based on official announcements and typical distribution flows.
The following Q&A is organized using the public info (release date: Friday, February 27, 2026) as the baseline.

Q1: Will it be available for streaming right after release?

A: In most cases, digital distribution (rental/purchase) starts after a certain period following the theatrical release (February 27, 2026).
In many examples of theatrical anime, rentals begin about 1–4 months after release, and subscription unlimited viewing often follows within several months to about a year.
So it may not be available immediately after release, but including rentals, there’s a strong possibility it can be watched within a few months after opening.

Q2: Is it okay to watch with kids? Are there age restrictions?

A: This series has long been produced for families, and this time as well, it’s expected to be released as a film that children and families can safely enjoy.
It’s unlikely that an official age restriction will be applied, but when watching in theaters, consider a young child’s attention span and the loudness of the sound.
If there are emotional or tense scenes, giving a light, simple explanation beforehand can help kids watch with confidence.

Q3: Will there be English subtitles or dubbing? Will it be released internationally?

A: Many releases are initially developed for domestic Japanese-language distribution, but if an international release or overseas streaming is decided, there is a high likelihood that English subtitles or dubbing will be provided.
Whether it expands internationally depends on the distributor/streaming company, and any overseas release would be announced on the official site.
It’s uncertain whether English subtitles will be available immediately in Japan, but support is often added later in streaming versions.

Q4: Any points to watch out for with theater bonuses or advance tickets?

A: Advance tickets vary by theater in terms of sale start dates (many theaters start from December 5, 2025) and whether bonuses are included.
Bonus items are often limited in quantity and may end early, so if you want a specific bonus, buying right after sales begin is the surest option.
Also confirm the redemption method, redemption deadline, and how to receive bonuses at the theater.

Q5: Which is the better deal—digital rental or subscription unlimited viewing?

A: If you want to watch early, rental (digital rental or disc rental) is the fastest approach.
However, if you’ll share with multiple people or plan to watch other titles too, using a subscription’s free trial or monthly plan may reduce the per-title cost.
With services that grant first-time points (for example, U-NEXT), you may be able to rent it effectively for free, so choosing based on your viewing style is recommended.

Q&A is so helpful, kuma!
Mirukuma is on the “I want to watch ASAP, kuma” side, so I’ll aim for theaters or rentals, kuma~.
But “effectively free with points” is a dream too, kuma! Mirukuma will check both, kuma~!

Summary of Works Featuring the Main Cast

We’ll summarize representative past works by main character.
Under each title, we’ve placed an Amazon search link to help you quickly check viewing or purchase options.
If a title interests you, use the link to confirm availability and pricing.

Representative Doraemon (Character) Titles

As the central figure of the series, Doraemon plays a key role in many theatrical films.
From early classics to recent entries, the films where Doraemon shines are the essence of the franchise.

Examples of representative titles:

• Doraemon the Movie: Nobita’s Dinosaur

🔗 View Amazon search results for Doraemon the Movie: Nobita’s Dinosaur

• Doraemon the Movie: Nobita and the History of Space Exploration

🔗 View Amazon search results for Doraemon the Movie: Nobita and the History of Space Exploration

Representative Nobita (Character) Titles

Stories centered on Nobita often emphasize friendship and growth, making them relatable for kids.

• Doraemon the Movie: Nobita’s Treasure Island

🔗 View Amazon search results for Doraemon the Movie: Nobita’s Treasure Island

• Doraemon the Movie: Nobita’s Great Adventure in the South Seas

🔗 View Amazon search results for Doraemon the Movie: Nobita’s Great Adventure in the South Seas

Representative Shizuka (Character) Titles

Works where Shizuka plays an important role often emphasize friendship and kindness.

• Doraemon the Movie: Nobita’s Dinosaur

🔗 View Amazon search results for Doraemon the Movie: Nobita’s Dinosaur

• Doraemon the Movie: Nobita and the History of Space Exploration

🔗 View Amazon search results for Doraemon the Movie: Nobita and the History of Space Exploration

Representative Suneo & Gian (Characters) Titles

Suneo and Gian add depth through comedic banter and conflicts, and they appear across many theatrical films.

• Doraemon the Movie: Nobita’s Treasure Island

🔗 View Amazon search results for Doraemon the Movie: Nobita’s Treasure Island

• Doraemon the Movie: Nobita’s Great Adventure in the South Seas

🔗 View Amazon search results for Doraemon the Movie: Nobita’s Great Adventure in the South Seas

Guest Voice Actor / Promotional Ambassador (El Role / Airi Taira)

According to the official announcement, the first guest voice actor reveal includes a guest role as El, a soldier living under the sea.
Also, the appointment of Airi Taira as the promotional ambassador further boosts the film’s buzz.
Checking the guest performers’ past works and related media can add enjoyment, including from the perspective of voice performance.

• Related video works and appearances by Airi Taira (search example)

🔗 View Amazon search results for Airi Taira

Let’s preview the voices by watching past works, kuma!
Mirukuma will watch a collection of Doraemon’s best scenes and get emotional, kuma~.
I’m excited about Airi Taira’s participation too, kuma~!

Recommended Similar and Related Works

Here are carefully selected works with themes and scale similar to Doraemon the Movie: Nobita’s New Undersea Devil Rock Castle, including past undersea adventures and family-friendly related movies.
Under each title, we’ve included an Amazon search link for checking viewing/purchase options.

Past Doraemon Works Featuring Undersea Adventures

Within the series, works set under the sea are easy reference points to compare directly with this film.
They’re ideal for enjoying how the “New” version reinterprets the “original” work.

• Doraemon the Movie: Nobita’s Undersea Devil Rock Castle (1983 version)

🔗 View Amazon search results for Doraemon the Movie: Nobita’s Undersea Devil Rock Castle

The 1983 original is a full-scale adventure featuring an undersea city and mysterious elements.
Watching it alongside the “New” version lets you enjoy differences in settings and evolution in direction.

Family-Friendly Animated Movies About the Sea and Adventure

These are works with strong ocean depiction, adventure thrills, and family resonance points.
They can also serve as comparison references for visuals and direction.

• Ponyo

🔗 View Amazon search results for Ponyo

A warm story about the sea and a child’s growth. It’s a good comparison in terms of undersea expression and family-oriented messaging.

• Castle in the Sky

🔗 View Amazon search results for Castle in the Sky

As a work that depicts the scale of adventure and the joy of discovery, it pairs well as a comparison to Doraemon’s big-adventure style.

Recommended Adventure Movies for Family Viewing (Similar Vibe)

From adventure movies that both adults and kids can enjoy, we selected titles especially suitable for family viewing.
Their story pacing and emotional construction share elements in common with this film.

• Studio Ghibli works (examples: My Neighbor Totoro, Princess Mononoke)

🔗 View Amazon search results for My Neighbor Totoro

Works grounded in nature depiction and family love have strong affinity with Doraemon’s family-oriented emotional lines.

• Family-friendly adventure picks (example: Nobita’s Treasure Island)

🔗 View Amazon search results for Doraemon the Movie: Nobita’s Treasure Island

A work with brisk adventure pacing and parent-child resonance points. It shares kid-friendly excitement and themes of family bonds.

Let’s watch similar works to get ready, kuma~!
Comparing the original Undersea Devil Rock Castle with the new one makes the differences fun, kuma~.
Mirukuma loves Ponyo’s ocean visuals, kuma~!

Check Social Media Buzz and Reviews!

We independently analyzed reactions on social media following the trailer release and the announcement of the promotional ambassador, and scored them across five evaluation parameters.
Each item reflects a comprehensive judgment of fan expectations, visual impact, family appeal, and more.

Five Parameters (20 Points Each)

• Anticipation: 18/20
  With the trailer and the release date announcement (Friday, February 27, 2026), expectations among fans and families are extremely high.
• Visual Impact: 18/20
  The freshness of an undersea setting is being praised. Many comments mention the beauty of the trailer’s visuals.
• Voice Acting / Cast Reaction: 16/20
  The announcement of guest voice actors and the promotional ambassador (Airi Taira) has created buzz, but not all guest cast details have been revealed yet, so it doesn’t reach a perfect score.
• Family Appeal (Fit for Families): 20/20
  The franchise’s hallmark expectation of being “fun for the whole family” is very strong, and reactions from family audiences are especially positive.
• Buzz Factor: 17/20
  The ambassador appointment and trailer release have boosted attention, but there are also comments about competition with other big titles and waiting for more details.

Total Score (out of 100): 89

Common Social Media Comments (Summary)

Positive comments: Many people say they’re excited by the scale and undersea depiction in the trailer, became interested because of the promotional ambassador, and want to see it with family.
Negative/concerned comments: Some worry that details about guest voice actors and the core of the story are still unclear, and some note that preferences may split when comparing it with past works.

Short Summary

On social media, there are many positive reactions and high anticipation, while many are also waiting for additional cast announcements and story details.
As the release date (Friday, February 27, 2026) approaches, the buzz is expected to grow further.

Social media reactions are fun, kuma~!
Mirukuma is happy feeling everyone’s excitement, kuma~.
There’s still more info to come, so keep checking announcements, kuma!

Conclusion: The Fastest Route to Watch in Theaters or Watch Cheap via Streaming

We’ll explain how to make the most of the theatrical release (Friday, February 27, 2026) and concrete steps to watch as cheaply as possible via streaming/rental afterward.
Understand both the benefits of theaters and the cheap viewing routes after distribution starts, and choose the fastest path that fits you.

Benefits of Watching in Theaters

The biggest benefit is immersion and presence.
The undersea visuals on a big screen and the sound direction can’t be fully replicated at home.
Watching right after release is also a high-buzz experience and can become a shared memory for parents and kids.
If you secure advance tickets early (sales begin in many theaters on Friday, December 5, 2025), you may get bonus items and better seat options.

How to Watch Super Cheap or Almost Free via Streaming

If you miss theaters, the fastest steps to watch cheaply are as follows:
1) Aim for rental streaming (about 1–4 months after release). Rentals are the fastest way to watch via streaming.
2) Use U-NEXT’s first-time trial and the granted points. Renting with points can make it effectively free in many cases.
3) Use TSUTAYA DISCAS mail rental to watch on disc, which can be an early and cheap option.
4) Use ABEMA and other VOD free trials/campaigns. Depending on the platform, some titles may be free with ads.
5) Check Amazon Prime Video rental sales and point-reward campaigns. Prime perks can sometimes reduce cost.

Future Distribution Checklist (Reader Actions)

• Right after release, check theater info and buy advance tickets.
• Because release timing differs by service, sign up for new release emails or follow official accounts for the VOD services you care about.
• Prepare to use services like U-NEXT and ABEMA that offer first-time trials and point grants.
• After rental starts, compare rental prices across Amazon Prime Video and other VOD services.
• If you prefer discs, check TSUTAYA DISCAS trial options and reservation status.

If you want the shortest route to watch cheaply, it’s realistic to start with U-NEXT points → digital rental, or consider TSUTAYA disc rental.
If you want to watch as early as possible, theaters are the first choice.

That’s the summary, kuma~!
Mirukuma is thinking: watch on opening day in theaters, then watch again with the family later using U-NEXT points, kuma!
If you want free or super cheap, don’t forget to use trials and points, kuma~!

🔗 View Amazon search results for [Doraemon the Movie: Nobita’s New Undersea Devil Rock Castle]

Alright, we’re ready, kuma! First, write the release date (February 27, 2026) on your calendar, kuma~!
Whether you watch in theaters or watch cheaply via streaming, Mirukuma will stick with you and help you decide, kuma~.
If you’re a theater person, check advance tickets, kuma. If you’re a streaming person, don’t forget to use trials and points, kuma~!
Mirukuma is cheering for you, kuma~! Can’t wait for Nobita’s New Undersea Devil Rock Castle, kuma~!