During a battle against Destron's forces, Shiro Kazami helps a priest who has been attacked by the evil organization's kaijin Hasami-Jaguar. Little does he know that the church where the priest resides is a front for a Destron hideout. After finding out the organization's latest motive, Kamen Rider V3, along with the Double Riders, must stop Destron from detonating a nuclear bomb in Tokyo.
* 1973: Kamen Rider V3 vs. Destron Mutants
A physicist named Tetsuo Okita discovers a new mineral called "Satanium," which is more powerful than uranium and emits destructive effects to anyone exposed to it. However, Destron abducts Okita in hopes of finding the source of Satanium and collecting more of it to expedite their run for global domination. Kamen Rider V3 must act fast in rescuing Professor Okita and preventing Destron from collecting more of the deadly mineral.