Doraemon Vol. 4: Nobita and the Castle of the Undersea Devil

**Doraemon: Nobita no Kaitei Kiganjo** (Japanese: ドラえもん のび太の海底鬼岩城?), officially known as Doraemon: Nobita and the Undersea Castle, is a 1983 science fiction anime film directed by Shibayama Tsutomu, part of the Doraemon manga and anime series. This is the fourth feature film in the Doraemon anime series, inspired by the legends of the lost continents Mu and Atlantis by creator Fujiko F. Fujio. Before its official release in March 1983, the full story was serialized in *CoroCoro Comic* magazine, published by Shogakukan. It was later released as a tankōbon volume that same year, becoming the fourth installment of the *Doraemon Long Story* series.

The film follows Nobita and his friends on an undersea adventure. Jaian and Suneo, motivated by news of a ¥20 billion treasure, break away from the group to find the ship containing the fortune. Meanwhile, the rest of the group, aided by the limited use of Doraemon’s *Adaptation Lamp*, discovers the existence of the ancient Mu continent’s inhabitants. These residents are trying to destroy the dangerous Poseidon, and the group decides to help in their mission.