One day, Nobita (voiced by Ohara Megumi) accidentally discovered the teddy bear that his grandmother sewed for him in his childhood, so he begged Doraemon (voiced by Mizuta Wasabi) to go to the past to visit his grandmother (voiced by Miyamoto Nobuko) who is no longer in this world. After Nobita reunited with his grandmother, his grandmother hoped to see what Nobita would look like when he grew up and got married. Nobita and Doraemon agreed to his grandmother's request and returned to the future again. On the day of the wedding as scheduled, everyone was present, but the most important groom, adult Nobita (voiced by Tsumabuki Satoshi), was not there. In desperation, Doraemon asked Nobita to pretend to be his adult self and marry Shizuka (voiced by Kakazu Yumi), but where did the real adult Nobita go?