The upcoming 45th Doraemon feature film, officially titled Doraemon the Movie: Nobita and the New Castle of the Undersea Devil, is set to premiere in Japanese theaters on February 27, 2026. While new visuals, setting art, and cast details for this highly anticipated remake have been released, there has been no official announcement regarding the film’s theme song, nor any indication of the band sumika performing it, in the currently available information.
Nobita and the New Castle of the Undersea Devil Set for February 2026 Release
The 2026 Doraemon film, Doraemon the Movie: Nobita and the New Castle of the Undersea Devil (Japanese: 映画ドラえもん 新・のび太の海底鬼岩城, Hepburn: Eiga Doraemon Shin Nobita no Kaiteiki Ganjō), marks the 45th installment in the beloved franchise. It is a modern reimagining of the classic 1983 film, Doraemon: Nobita and the Castle of the Undersea Devil. The film is directed by Tetsuo Yajima, with the screenplay penned by Isao Murayama, who has previously contributed to the Doraemon TV series.
The new film is slated to debut on February 27, 2026, promising a fresh take on an iconic underwater adventure.
Plot Diving Deep into Undersea Mysteries
The story of Doraemon the Movie: Nobita and the New Castle of the Undersea Devil will once again immerse audiences in an aquatic escapade. Doraemon and friends—Nobita, Shizuka, Gian, and Suneo—embark on an underwater camping trip utilizing Doraemon’s advanced gadgets. Their journey takes an unexpected and perilous turn as they venture beyond their initial plans, discovering the hidden underwater Kingdom of Mu.
Upon their discovery, the group is captured by the inhabitants of Mu, who are fiercely protective of their secrecy from the surface world. There, they encounter a young boy named Eru, voiced by Shoya Chiba, a soldier from the Mu Federation. Together with Eru, Doraemon and his friends uncover a significant threat emanating from the robotic-controlled Kingdom of Atlantis. A supercomputer named Poseidon, in control of Atlantis, intends to launch nuclear weapons against the surface world, mistakenly perceiving a volcanic eruption as an invasion. The team must race against time, leveraging Doraemon’s various secret gadgets, to thwart Poseidon’s plans and safeguard both the land and undersea worlds. Ryo Hirohashi also joins the cast as the voice of the Underwater Buggy, one of Doraemon’s essential amphibious gadgets for this adventure.
No Current Announcement for sumika’s Theme Song
Despite the anticipation surrounding the 2026 film’s release and the unveiling of its plot and visual elements, official reports and promotional materials released to date have not yet revealed the film’s theme song artist or title. Specifically, there has been no information confirming that the popular Japanese band sumika will perform the theme song for Doraemon the Movie: Nobita and the New Castle of the Undersea Devil. Past Doraemon films, such as the 2025 film Doraemon the Movie: Nobita’s Art World Tales, featured songs by Aimyon. However, details regarding the musical contributions to the 2026 installment are still pending an official announcement.
