Nobita Nobi, a student in elementary school, doesn't enjoy studying or have athleticism, and his approach to things lacks enthusiasm. His shyness and poor luck make it difficult for him to achieve success, and his future descendants have the same fate. When Nobita's distant descendant, Sewashi, decides to take action, he travels back to the 20th century from the 22nd century to meet with Nobita. Nobita is shocked to see Sewashi show up with a blue robotic cat named Doraemon. Sewashi's true purpose for setting up this encounter is for Doraemon to assist Nobita and bring him happiness. Doraemon is determined to help Nobita by using his modern technology that he keeps in his four-dimensional pocket that can solve any of Nobita's issues. At first, Doraemon thinks about returning to the future because of Nobita's hopeless situation. But, Sewashi forces Doraemon to stay by activating a program that prohibits him from leaving. Will Doraemon be able to make Nobita's life happy and be able to go back to his own time?