Kamen Rider Gaim was part of the Kamen Rider Series; it is the 15th series during its Heisei run and 24th overall. The series, written by Gen Urobuchi, directed by Ryuta Tasaki and produced by Naomi Takebe, began airing on TV Asahi from October 6th 2013. It ran for 47 episodes.
In Zawame City, a large company known as the Yggdrasill Corporation transformed the once bustling suburban city into a jōkamachi. To escape the resulting feeling of oppression, many of the youth in Zawame formed dance crews called Beat Riders to bring joy back into peoples’ lives.
Also rising in popularity is the Inves Game, a simulator that uses strange devices known as Lockseeds to summon monsters known as Inves. Kouta Kazuraba, a member of the dance group Team Gaim, tries to find his place in the world while torn between his loyalty to his teammates and his sister Akira’s insistence that he starts acting like an adult and find a proper job. When Team Gaim’s captain disappears after informing Kouta of a strange belt he found, Kouta discovers that the Lockseeds and Inves are from an alternate dimension known as Helheim Forest.
Encountering a mysterious girl resembling his Team Gaim teammate and close friend Mai Takatsukasa, Kouta uses a Sengoku Driver belt and the Orange Lockseed to become a samurai-armored warrior that is later named Armored Rider Gaim.
In time, including Team Baron’s leader Kaito Kumon as Armored Rider Baron and Kouta’s Team Gaim teammate Mitsuzane Kureshima as Ryugen, other Armored Riders appear to amass social power throughout Zawame: Team Raid Wild’s Ryoji Hase as Kurokage, Team Invitto’s Hideyasu Jonouchi as Gridon, and the perfectionist ex-soldier Oren Pierre Alfonzo as Bravo. Unbeknownst to the Armored Riders, the Yggdrasill Corporation monitors them and the Inves Games while the head of its R&D division, Mitsuzane’s older brother Takatora, is the enigmatic white Armored Rider Zangetsu who is protecting a dark secret hidden within Helheim Forest.
Eventually, when Kouta confronts Takatora as he becomes a New Generation Armored Rider alongside the Armored Rider development scientist Ryoma Sengoku as Duke, his aide Yoko Minato as Marika, and the Lockseed Dealer Sid as Sigurd, he learns the horrible truth of Helheim Forest: that it was home to a once prosperous civilization that was eradicated by the strange plants growing throughout it, as anyone who consumed the fruit of these plants is turned into an Inves. Finding an ally in DJ Sagara, a pirate radio DJ who knows more than he is letting on such as the intelligent Over Lord Inves, Kouta finds himself in the middle of a Sengoku period-like brawl among various factions for the right to possess the power of Helheim Forest–the proverbial forbidden fruit itself–and the fate of life on Earth as he knows it. But while adamant to obtain the Golden Fruit to save the world, Kouta’s goal involves him having a predestined confrontation with Kaito who desires the fruit’s power to shatter the status quo of the world.