The micronauts first adventure begins with the escape of Prince Argon and his sister Mari. Children of the royal family of Homeworld, they saw their parents slain by their own citizens, led into insurrection by their former chief scientist, the Baron Karza.
With some guards still faithful, they are able to escape. They are pursued by the Dog soldiers of Baron Karza and the acroyear warriors of Karza's ally, prince Shaitan. They find a place to hide and Argon shows his little sister that he has summoned the Enigma force in order to help them. Unfortunately, their hiding-place is found and Argon is shot. Still alive, he is taken to the body-banks of Karza.
Some time later, the first space traveler, Commander Arcturus Rann, lands in Homeworld after 1000 years in suspended animation. He was surprised by the Dog soldiers and, after being shot, he wakes up in a cell.
In it, he meets Prince Acroyear and the master thief, Bug of Kaliklak. They explain to him that, during his travels, faster-than-light space travel was discovered and so, his 1000 years travel was useless. He also discovers that his professor, 1000 years ago, is the new ruler of his planet, the Baron Karza. Soon after, the three heroes were led into the huge arena, under the sight of Karza. Assisted by a robot, a beautiful blond girl plays as a marionette in the place. It’s the Princess Mari (and her tutor-robot Microtron), They have become members of the Homeworld underground and already allies of Acroyear and Bug.
The battle begins between the Micronauts and a Deathtank, a giant and dreadful robot.
Thanks to the strength of Acroyear and to the hidden weapon of Bug , they destroy the tank meanwhile some bombs, put by the underground, explode in the stands. The strange apparition called Enigma force shows himself a second time, saying to Rann it’s time to run. Commander Rann, Mari (now called as Marionette), Acroyear and Bug escape from the arena. After joining his space ship, the HMS Endeavor, and his personal and friendly robot Biotron, Rann decides to go through the outer limits of the microverse, preventing his new companions from being killed.
The micronauts are born.