Sequel to the 2018 animated series SSSS.Gridman and the third installment of the Gridman multimedia franchise.

When Yomogi Asanaka, a first-year student at Fujiyokidai High School, meets Gauma, he claims to be a "kaiju user." But the appearance of a kaiju followed by the entry of the gigantic robot, Dynazenon, backs up his mysterious words. After ending up in the wrong place at the wrong time; they get dragged into the desperate fight against the kaiju!