Kamen Rider Zi-O (仮面ライダージオウ Kamen Raidā Jiō) is a Japanese tokusatsu drama in Toei Company‘s Kamen Rider Series. It is the twenty-ninth television series overall, as well as the twentieth and final series in the Heisei period. Toei registered the Kamen Rider Zi-O trademark on May 5, 2018. The show premiered on September 2, 2018, following the finale of Kamen Rider Build, joining Kaitou Sentai Lupinranger VS Keisatsu Sentai Patranger and later, the miniseries Super Sentai Strongest Battle, followed by Kishiryu Sentai Ryusoulger in the Super Hero Time line-up. Much like its spiritual predecessor Kamen Rider Decade, it commemorates all of the Heisei-era Kamen Riders to date via the means of traveling through time, hence the show’s time travel motif; with a slight multiverse motif similar to said predecessor.
Sougo Tokiwa, a high school student born in the year 2000, dreams of one day becoming a king when he meets a mysterious girl named Tsukuyomi from the year 2068 who gives him an ominous warning: “You will become Kamen Rider Zi-O, the King of Time; the demon destined to rule the world.” While troubled by his possibly cursed fate, Sougo becomes Zi-O to save the time space continuum from the Time Jackers, a group seeking to alter the history of the Heisei Kamen Riders for their own purposes. He is also aided by Geiz Myokoin, a resistance fighter from 2068 who becomes Kamen Rider Geiz and initially intended to kill Sougo to prevent the tyranny of Oma Zi-O, and a self-titled prophet named Woz who wants the youth to become Oma Zi-O, who later gains the power to transform into Kamen Rider Woz. During their journey, Sougo and his friends meet several Kamen Riders from the past and their allies, earning their trust and obtaining their powers while seeking to create a new future for both the Kamen Riders and mankind itself.