Doraemon the Movie: Nobita's Great Battle of the Mermaid KIng

Synopsis

In "Doraemon the Movie: Nobita's Great Battle of the Mermaid King," Nobita requests Doraemon to take him diving, prompting the robotic cat to use several gadgets to create a simulated ocean high above the ground. When the illusion is deactivated, a mermaid unexpectedly appears in Nobita's backyard. Introducing herself as Sophia, she reveals she is a princess from an ancient underwater civilization. Doraemon, Nobita, Shizuka, Gian, and Suneo quickly become friends with her and are invited to explore her undersea kingdom. However, on their way there, they become involved in a conflict between the mermaids and a rival tribe that drove them from their original home planet thousands of years ago. Together, Doraemon, Nobita, and their friends must help Sophia find a legendary sword that may bring peace back to the oceans.