One day after school, first-year high school student Yomogi Asanaka comes across a starving man under a bridge. Introducing himself as Gauma, the strange drifter informs Yomogi that he is a kaiju user, a person who deals with the kaiju—monsters who bring harm to the city and its citizens. The following evening, Yomogi runs into Gauma and his classmate Yume Minami. Simultaneously, a kaiju appears in a populated area of the city. Due to Gauma's lack of experience controlling the kaiju, he brings out a mysterious object from a glowing pouch, summoning a giant robot known as Dynazenon. Requiring the cooperation of four people, the mecha drags Gauma, Yomogi, Minami, and Koyomi Yamanaka—an unemployed man who was wandering on the street—into its cockpit. Their encounter with the kaiju marks the beginning of their entanglement with kaiju eugenicists—kaiju users who manipulate kaiju with ill intent—and their efforts toward bringing out the full potential of Dynazenon.

Nobita Nobi is an elementary student who hates studying, is bad at sports, and does everything half-heartedly. He is a pushover, unlucky, and fearful of many things. His personality makes him a failure in life, even affecting his progeny. This causes his great-great-grandchild, Sewashi, to take control of the situation. Sewashi travels back in time from the 22nd century to the 20th century to meet Nobita, who is shocked to see him appear out of his drawer alongside a blue robotic cat. The robotic cat calls himself Doraemon, who claims to have been pressured by Sewashi to assist Nobita, with their ultimate goal being to provide Nobita happiness. Frustrated after seeing Nobita's hopeless state, Doraemon decides to go back to the future. However, Sewashi activates a program within Doraemon that prevents him from doing so. Forced to stay, Doraemon helps Nobita using futuristic gadgets through his four-dimensional pocket—a bag containing anything inside it. Can Doraemon bring Nobita happiness and return to the future?

Star Driver takes place on the fictional Southern Cross Isle. One night, a boy named Takuto washes up on shore swimming from the mainland. He later enrolls in Southern Cross High School as a freshman and makes new friends. (Source: Official website)

After reminiscing about his late grandmother, Nobita Nobi wishes to see her again and asks Doraemon to return them to the past. Following the wholesome reunion of the two, Nobita's grandmother confesses that she hopes to meet his future bride. Nobita accepts her request out of filial love and quickly scrambles into the time machine as he and Doraemon journey forward in time. However, when the duo warps to Nobita's wedding day, they discover that the future Nobita is missing from the ceremony! Determined to set things right, Doraemon and Nobita embark on a mission to search for Nobita's future self and encourage him to discover the happiness he deserves.