Doraemon is kidnapped by a criminal group targeting caretaker robots, just before his birthday, forcing Nobita, Shizuka, Gian, Suneo, Dorami, and Sewashi to launch a rescue mission. As they uncover a conspiracy involving robot trafficking and a rogue factory manager at Matsushiba Factory, they learn Doraemon risks being reset and losing his memories. Fighting through security drones, mechanical traps, and the crab-like captor, they reach the factory’s core just as Doraemon is about to be erased. In the end, the manager cancels the reset, Doraemon is saved with his memories intact, and he reunites emotionally with Nobita before they return home together.

On a cold snowy day, Nobita learns that Doraemon must return to the 22nd century, which leaves him devastated. Despite his initial denial and emotional outburst, including yelling at Doraemon and running away, he slowly begins to understand the situation after his father explains that Doraemon also suffers when Nobita is sad. Realizing he needs to become independent, Nobita accepts the separation. Later, he and Doraemon share a final emotional moment, remembering how they first met and promising to move forward. Doraemon, deeply moved, cries as he leaves, proud of Nobita’s growth.

It's the birthday of the cat-shaped robots, and Dorami and Sewashi are searching a present for Doraemon in the 22nd century. But during a chain of gas attacks on the cat robots under a scheme to replace them with dog robots, Dorami is wrongfully taken away, so Sewashi goes to the dog robot factory to protest against the decision. Back in the 21st century, Nobita gets a new robot companion, Wonderful, who watches over him as he does his homework. A group of breakaway cat robots led by Pawaemon take Doraemon into hiding, but when the latter accidentally causes the others to get sent to scrap, he is left on his own as Nobita goes back to the future to save Doraemon and all the cat robots.

Nobita, inspired by Suneo’s stories about Egyptian pyramids and hidden treasures, decides to travel to Egypt with Doraemon using futuristic gadgets like the Anywhere Door and Time Belt. There, they discover a royal tomb and meet Nemses II, a young pharaoh who reveals he was betrayed and trapped by a usurper named Warueheb. After bringing Nemses back to the present to understand the situation, Nobita and his friends (Shizuka, Gian, and Suneo) return to ancient Egypt to help him reclaim his throne. They soon realize Warueheb has used Nobita’s lost Future Diary to gain power and control over the kingdom. An epic adventure begins as they try to restore justice and save Egypt.