Shin Kamen Rider Prologue started development as soon as Black RX finished in 1989. Originally it was pitched in a Manga format similar to how ZX was, but that idea was quickly scrapped. Ishinomori's son, Joe Onodera, wrote a hook while his father worked separately on a synopsis for a new project: Kamen Rider Gaia. Eventually, Junichi Miyashita would join Onodera to develop a more proper script, taking some concepts from Ishinimori's Gaia work- some early iterations even had the main character called Gaia before settling upon Shin.
Rather than a series, a movie was proposed, and Toei's release of Lady Battle Cop in 1990 would help spur interest in developing a direct-to-video Kamen Rider film.
Some of the earliest ideas were a bit out there. The first was of a man Cosplaying Kamen Rider and is injured saving someone, eventually somehow becoming a real Kamen Rider. Producer Shinichiro Shirakura shot that down immediately, requesting something more traditional. Although Ishinomori seemed really intrigued by the original pitch.
Still, Ishinomori had to approve of the direction, and going back to basics again wasn't what he had in mind, at least not exactly. They already did that with Black, after all. If Black was a return to form and Rider 1 was the basis for which all others branched out, then Shin would be the roots of the metaphorical tree. A true Kamen Rider 0. Ishinomori wanted Onodera and Miyashita to explore the Kamen part- the mask and the horror it hides. Resulting in a Rider without a suit or belt, the monster lay bare in its most basic iteration.
Now, Shin is a bit of a unique thing to review because it's technically incomplete. This was meant to be the opening to something that might've had two to four more parts, hence the prologue. That said, I can still review this for what it is- which is an introduction laying the groundwork. Now, let’s get into this properly.
Kamen Rider Shin primarily follows Shin Kazamatsuri (Katsuhisa Ishikawa) a former motorcycle racer who has given up his dream to assist his father, Daimon Kazamatsuri (Akira Ishihama) a geneticist working for The Institute of Super Science Technology (ISS) on enhancing humans to overcome various diseases and ailments- Shin being their greatest success yet.
