Sougo Tokiwa seems like an ordinary high school student, but one thing he has different is that he has dreams of becoming a king! One day, a mysterious young man appeared before him with a prophecy. "Congratulations! Today is a special day for you..." As Sougo is told these words, a giant red robot suddenly appears before him! This robot was a time machine, and Sougo was thrust across various timelines! In the year 2000, the battle of the Heisei Rider's fate, and Sougo's fate in his own birth year, is about to begin...!
The man who hails from the future, Geiz, attacks Sougo! Tsukuyomi, a girl who also hails from the future, came to help out Sougo, but Sougo has absolutely no idea what's going on! A mysterious prophet named Woz is also starting to appear frequently before Sougo. The creature, Another Build also attacks. What could be the key to defeating this "Kamen Rider Build"? Sougo makes his way towards the Nascita Cafe to meet with Kiryu Sento...
A strange collaboration between Geiz and Tsukuyomi happens with Sougo in the year of Build, 2017. They both decide to go to Sougo's school to keep a closer eye on him. While there, they discover a growing popularity of a "game that no one can clear" with the other students. Rumors surrounding the Genius Gamer M start to surface as well, as they decide to chase the mystery by finding him. And Sougo and the others end up meeting...? Suddenly, a new Time Jacker, Ora appears!
Ora has given a father the power of Another Ex-Aid as part of a bargain for his son's life. Geiz and Sougo travel back to 2016 to help him.
Tsukuyomi and Geiz learn that 18-year-old Libras have been going missing from Amanogawa High for years and want to check it out, thinking that it's probably an Another Rider plot; Schwartz makes his presence known to Uhr and Ora, forcibly creating a new Another Rider.
Takumi joins Sougo in protecting Karin from Another Fourze; Tsukuyomi and Geiz learn that Karin is actually much older than she looks.
Sougo learns of a magic show and wants to check it out. After seeing the magician in action, Geiz believes that he might have been given the powers of Kamen Rider Wizard and wants to fight him.
Geiz tracks down Kousuke in order to get his hands on the Wizard Ride Watch.
Uhr gives Kuroto Dan the powers of Kamen Rider OOO, which leads to Kuroto declaring himself king in 2018. Sougo finds common ground with this new Kuroto and wants to learn from him.
Sougo asks Kuroto just what type of king that he wants to be; Tsukuyomi learns to listen to all points of view.
Sougo and Tsukuyomi search for Geiz when Sougo notices the news that Team Baron dancers have been disappearing, but Tsukuyomi gets fed up with Sougo constantly returning just after leaving and having an inconsistent memory.
Sougo is revealed to have traveled back in time to save Geiz, and so there are two of him in the present, but Woz isn't very keen on this plan.
Takeru Tenkuuji and company have been hired by a woman to investigate Another Ghost after her brother mysteriously disappeared; a confrontation occurs with what appears to be Kamen Rider Agito.
With Sougo's soul separated from his body, he guides Takuru back to the year 2015 where Geiz has his Ghost watch taken from him in exchange for a Decade one.
Oma Zi-O sends a fleet of Dai Mazine to 2018 and a loyal follower to take out Geiz and Tsukuyomi; Tsukasa sends Sougo to meet his future self.
Sougo returns from the future and destroys his belt, ensuring that he will not become Oma Zi-O, but he is later attacked with no one to turn to for help.
Sougo has a dream that he is in the year 2022 and meets a man who goes by Kamen Rider Shinobi. Later, he encounters an Another Rider with the same attacks and a second Woz appears.
Sougo and crew are confused over the appearance of "White Woz"; Geiz and Tsukuyomi try time traveling to get the Kamen Rider Shinobi watch but are forbidden to land.
Sougo and Geiz head into battle with an Another Rider when the original Rider also arrives on the scene. How are both Kamen Rider Quiz and Another Quiz active at once?
Sougo works with Mondo to get answers from his dad and Geiz works with "White" Woz to stop Another Quiz.
Heure breaks a mirror and gives an Another Rider watch to a man inside; Sougo and Geiz have trouble defeating an enemy who keeps retreating even though he has nowhere to run.
Sougo battles with his self on the other side of the mirror; Geiz tries defeating Another Ryuga when things go horribly wrong.
Sougo falls asleep while studying and travels 100 years into the future to a world where humans and machines are at war; Tsukuyomi joins forces with White Woz.
Sougo dreams of Kikai going evil while Ora asks White Woz for help with Heure; Geiz asks Tsukuyomi if she really wants to align herself with White Woz.
A man with a connection to Sougo's past is taking the leftover energy from previous Another Riders.
Tsukuyomi travels back in time to investigate Hiryuu Kakogawa; White Woz tells Geiz that his watch won't activate until he's committed to killing Sougo.
After getting beat by Geiz, Black Woz goes to Ora and Heure for help; Schwartz recalls the first time he met Tsukuyomi.
Tsukuyomi learns about Sougo's past; Sougo and Geiz prepare for their showdown.
Kamen Rider DiEnd runs off with Sougo and Geiz's watches when Tsukuyomi gets word of Another Blade; Sougo forces Woz and Geiz to work together.
White Woz has Blade and Chalice fight to bring on the end of the world; Black Woz and Geiz settle their differences.