The story begins with a regular day with Takumi, Mari and Keitaro, which suddenly turns into a musical number thanks to a mysterious new boom box created by Smart Brain. As it turns out, Yuji, Yuka and Naoya have the same boom box and are greeted by a rapping Smart Lady who reveals that it's part of a new plan by Smart Brain to invoke people into singing all over Japan. The reason: To get the three Rider Belts back!

The Smart Brain corporation, the world's most powerful corporation, is trying to take over the world using Orphnoch, the "next stage in humanity's evolution", to covertly kill off the human population. In pursuit of this, they develop three suits of power armor, called Rider Gears (each for Faiz, Kaixa, and Delta), to find and protect the Orphnoch King, who can fix a defect within Orphnoch DNA which causes their genetic structure to break down, leading to death."

A video version of the original Kamen Rider manga.

In the near future, the world is ruled by the Smart Brain Corporation, with 90% of the population being Orphnoch, and the once prominent human race is nearing extinction. Takumi Inui, Kamen Rider Faiz, was once regarded as mankind’s savior until, in an attack by Smart Brain troops, he was presumed dead. Since then, human rebel groups have staged attacks on Smart Brain’s complex in an attempt to steal the top-secret Emperor Belts, with no success. Kiba Yuji, Naoya Kaidō and Yuka Osada attempt to ease tensions between both races but their peace meeting is interrupted by Smart Brain troops and their newest warrior, Kamen Rider Psyga. Takumi, believing himself a young cobbler named Takeshi, regains his memory and becomes Kamen Rider Faiz again to settle things with Smart Brain once and for all.

Takumi, Mari, Masato, and many other people who work at Kikuchi Cleaning Shop are leading their daily lives as usual. One day, a customer visiting the store is suddenly killed by someone, they need to try to find out who the murderer is...

Arata Kagami seeks to get the Hyper Zecter just like Souji Tendou, so he tries to emulate Tendou. Once he realizes that he has to be himself, the Hyper Zecter appears and allows him to transform into Kamen Rider Gatack Hyper Form.

Released to commemorate Kamen Rider 555's 20th anniversary, the film takes place after the ending of the TV series. Masato Kusaka and Mari Sonoda are fighting a new iteration of Smart Brain led by Kitazaki, who begins an operation to exterminate all Orphnochs, with Takumi Inui seemingly working with them for unknown reasons since his disappearance.

Doctor Keitaro Shido, an acclaimed scientist, has been kidnapped by the terrorist organization Neo-Shocker to exploit his expertise in robotics technology. Desperate to escape, he convinces Neo-Shocker's command to allow him to operate on an injured camper. Explaining that he can turn the camper, Hiroshi Tsukuba into a powerful Neo-Shocker warrior, they allow Doctor Shido to operate. However, he quickly turns the tables on them, transforming Hiroshi, not into a kaijin, but the powerful warrior Sky Rider, using his newfound abilities to combat the evil Neo-Shocker menace.

The Igarashi siblings travel to the forbidden Area 666 to rescue airjacking victims (including their parents!) from the dangerous criminal known as Azuma, who wishes to judge the fate of humanity himself.

Geats, Revice, and Ryuki wage a fierce battle royale that transcends beyond the Heisei and Reiwa eras.