The book is released simultaneously with the movie "Doraemon: Nobita and the Castle at the Bottom of the Sea" (new version) from May 22, 2026. This is a year-end gift and opens up a summer journey full of wonders and emotions for young readers.
The story begins with Doraemon's plan to camp on the seabed and his friends Nobita, Shizuka, Jaian and Suneo. Thanks to the magical treasures, the group goes to the ocean, meets the deep-sea creature world, drives a buggy underwater, explores the Mariana Trench, encounters the mysteries of the missing 3-pole ship, MU Federation, Atlantis and the threat named Poseidon.
The captivating, dramatic story is pushed to a climax through each chapter from "It's summer, let's camp!", "Adventures in the Sea!", "The Deepest Bottom of the Earth!" to "Coming to the Castle of the Devil!" and "Saving Shizuka!".
The deep ocean with countless mysteries becomes a passionate summer school, turning children's curiosity into motivation to learn. New concepts such as continental shelf, continental slope, sea crevice, deep seas creatures, Mariana crevice... appear naturally in the adventure.
Those are "witness-witness" experiences, explained easily, and incorporated into an engaging story. The author skillfully encourages them to ask more questions, observe the world, and nurture their imagination and curiosity.
Besides the adventurous colors, the new version of "Doraemon: Nobita and the Castle at the Bottom of the Sea" is a song about friendship. In dangerous situations, the children do not seek safety for themselves but bravely confront each other. Doraemon is worried when Jaian and Suneo are in trouble, Shizuka stands up to protect Buggy Cung, Nobita tries to overcome his fear to go with his friends.
The friendship in the story is expressed by caring, willingness to admit mistakes, protect friends and take responsibility. Troubles arise when the characters act impulsively, are eager to find treasures and forget the danger. But it is from those mistakes that the children learn to admit mistakes, cooperate and grow up. In the final stage, when Shizuka is in danger and Poseidon threatens the world, the whole group advances to the demonic castle together, fight together, trust and protect each other.
Another layer of profound humanistic meaning of the book comes from the character Buggy Cung, which is the treasure of going underwater. Initially, it was simply a machine operating according to data and control commands, but through the journey with Nobita and his friends, Buggy gradually comes into contact with very "human" things from memories, emotions, worries, to gratitude, sacrifice and friendship.
The story is therefore not only about people exploring the ocean, but also a journey for a machine to learn how to understand the heart. Buggy Cung becomes the main character of the story, a true friend of the group. Victory over Poseidon is called "the victory of the heart", associated with solidarity, the spirit of not abandoning each other in difficult times and the desire to live peacefully together.
This summer, the robot cat Doraemon and his friend Nobita will dive into the deep blue ocean, unlocking their imagination to reach the vast world, where friendship and courage will help us defeat the most ferocious monsters.
