“The legacy of the Heisei Kamen Riders has carried on throughout the era. And now they pass their power on to the next generation! Rejoice, for the birth of a new king!”

Sougo Tokiwa who always dreamed of becoming a king encounters a mysterious girl who came from the future and warns him that he would become the king of all time, Kamen Rider Zi-O, who destined to rule the world.