Choujuu Sentai Liveman (1988 - 1989)

Yusuke, Jo, Megumi, Kenji, Gou and Rui are students at Academia but the latter three decide to turn bad and join forces with the evil army Volt. When the defectors return, their three friends are forced to combat them as Choujuu Sentai Liveman. With the help of an android ally named Colon and a few others along the way, the Liveman must save the world and their friends.