The movie was supposed to be followed by a TV series, plans for which fell through.
Before the name "Kamen Rider Shin" was decided, Shotaro Ishinomori originally planned for the character to be called "Kamen Rider Gaia". The design of this Kamen Rider Gaia was originally more of a traditional Kamen Rider appearance, before later designs switched to a "Kamen Rider Style Reform" version (resembling a man in a motorcycle helmet and modified riding jacket), and then the mutated insect-like human that would become Kamen Rider Shin.
The first Masked Rider movie done in Japan's Heisei era (1989-present).
The name of this film's Masked Rider, Shin (as well as his alter-ego, Shin Kazamatsuri), translates to "truth" or "real" (like "zen"). Not only because of the Buddhist zen/ai (truth and love) motif between Shin and his girlfriend Ai, but also a reference to this Rider being a "real" mutant grasshopper (as opposed to a grashopper-themed cyborg, as is the case with most past Riders). The only Rider from the Showa-era to share this characteristic is the titular Rider from Kamen Rider Amazon (1974) (only Amazon was not based on an insect).
This was the 20th Anniversary Masked Rider movie, and also Shotaro Ishinomori's anniversary gift for adult fans of the franchise.