Long ago, a powerful sentient robot known as GoLion, abused his great powers by attacking and killing creatures known as Deathblack Beastmen, boasting that no one could defeat him. For his arrogance, The Goddess of the Universe punished GoLion by separating him into 5 different lion robots. In the year 1999, a group of 5 young men returned to Earth after a space voyage, only to find it ravaged by nuclear war. After encountering the alien race known as the Galra, the 5 youths end up on the planet Altea and learn that the 5 lion robots that GoLion was split into are in hibernation in various parts of Altea. Somehow, they must reunite the lions and form GoLion, the only hope for the human race.

Weil ein gigantischer Asteroid droht, auf der Erde einzuschlagen, brechen einige Astronauten einer erdnahen Raumstation auf, den Himmelskörper vorher zu zerstören. Das Unternehmen gelingt, doch schleppen die Astronauten so einen gefährlichen außerirdischen Virus in die Station ein, die in rasender Geschwindigkeit zu tentakelbewehrten, einäugigen Kreaturen in Menschengröße mutiert, die dann beginnen, die Station zu überrennen. Gibt es eine Rettung?

Kamen Rider follows Takeshi Hongo and later, Hayato Ichimonji, both were turned into cyborgs by the evil organization called Shocker, but managed to escape before they were brainwashed by them. With the help of Tobei Tachibana and their friends, they fight the evil Shocker and later, GelShocker from their plans of world domination as Kamen Rider!

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当还是很和平的时候，世界突然出现了一个企图侵略地球的邪恶军团“黑暗十字军”，地球受到无尽的威胁。在这时，联合国组成了一支地球保卫联盟的军队。这支军队被分配到不同角落，其中一支就处于日本。“黑暗十字军”开始在日本不同地区破坏。
日本各地，黑暗十字军各自选出目标，杀害反对他们的人。当大家都被杀害，其中五人奇迹生还并发誓会复仇。他们穿上特别的电子战衣，使用着普通人没法使用的超能力。指挥官告诉他们，他们是秘密的战士·“秘密战队五连者”。具有很好的机会去对抗十字军。