The Kamen Rider Series (仮面ライダーシリーズ, translated as Masked Rider Series) is a franchise of manga and tokusatsu television programs and films created by manga artist Shotaro Ishinomori. The various Kamen Rider media generally feature a motorcycle-riding superhero with a varying motif who fights supervillains often referred to as kaijin (怪人). Generally, most Kamen Riders call out "Henshin!" during their transformation sequences. Variations of this phrase have been used by various Riders, either when transforming or switching between forms.
The franchise began in 1971 with the Kamen Rider television series which followed college student Takeshi Hongo and his quest to defeat the world-conquering Shocker organization. Over the years, the popularity of the franchise has grown and the original series has spawned many television and theatrical sequels. The cultural impact of the series in Japan resulted in Akimasa Nakamura naming two minor planets in honor of the series: 12408 Fujioka, after actor Hiroshi Fujioka, known for his portrayal of Kamen Rider, and 12796 Kamenrider, after the series, itself.