Kamen Rider Zi-O is a Japanese tokusatsu television series and the twentieth main entry in the Kamen Rider franchise. It follows Sougo Tokiwa, a high school student who learns he is destined to become the Demon King and the future Kamen Rider Zi-O. As he travels through time, he encounters previous Kamen Riders and their histories, using their powers while confronting enemies who seek to alter the timeline. The series blends time travel, legacy, and anniversary celebration.