Kamen Rider vs. Shocker

Kamen Rider The First is a 1971 Japanese tokusatsu Film. The film is a movie adaptation of episode 13 of the television series Kamen Rider.

Synopsis
Professor Daidōji (大道寺博士 Daidōji Hakase?) has developed a gravity machine called the GX Device. Unfortunately, Shocker wants it; so they attack the professor and destroy his laboratory, but come home empty-handed. Shocker's agents find out that the plans for the GX Device are with Daidōji's daughter, who is celebrating her birthday. Now the Kamen Riders, along with FBI agent Kazuya Taki, must protect Daidōji's daughter and prevent Shocker from obtaining the plans.