10,000 years ago, human folly lead to the Earth being split apart into two lesser halves. The Southern hemisphere dissappeared into the void of space, while life on it's Northern counterpart began to take a drastic turn; the few humans who were left evolving into an entirely new breed of homo sapiens with the ability to morph into anthropormorphic beast forms.

However, humankind as we know it didn't completely die out with the disappearace of the Southern hemisphere, as many of the humans who lived there managed to survive, protected from the harsh enviroment of space by the machinations of URANUS; and, now, 10,000 years later, they have managed to return to Earth in small numbers through Czar Master's floating colony; strangely enough, also named URANUS.

In the present of the KO Century, Beast Tribes worship idol statues called Jinn. The Jinn are also 10,000 years old, and the Beasts are sworn to defend them. A few of the tribes have Jinn Hearts which are worn by young members of the ruling family. Unbeknowst to the Beasts, the Jinn are actually robotic weapons, and the Jinn Hearts are a vague link to the actions of the Jinn, much like a remote control.

The evil ruler of URANUS, Czar Master, has captured the three Jinn who, together, hold the secret to unlocking GAIA's secret; and, as all stories must have plot devices, it so happens that these particular Jinn belong to the titular Three Beast Warriors.

Employing the scientific talents of Dr. Password, an expert on the powerful but dormant supercomputer GAIA, Czar Master's tries to unleash the powers of the three Jinn and find a way to activate the powerful GAIA NETWORK .

However, troubled by Czar Master's policy of exterminating all Beasts, Dr. Password knows much more than he's actually willing to share and, in particular, is fearful of informing Czar Master of his granddaughter's mysterious link to the GAIA NETWORK.