Sewashi and Doraemon find themselves way back in time and meet Nobita. It is up to Doraemon to take care of Nobita or else he will not return to the present.

Luca follows in his father's footsteps to rescue his mother from evil Ladja. Finding the heavenly hero who wields the Zenithian sword is his only hope.

A brother and sister learn their biological grandfather was a kamikaze pilot who died during World War II. During their research into his life, they get conflicting accounts from his former comrades about his character and how he joined his squadron.

Nobita travels to the future to show his beloved grandma his bride, but adult Nobita has fled his own wedding.