The research lab, situated on the barren planet of Xarbia, has been experimenting with genetic engineering in an attempt to improve crop yields for the nearby colonies. One of these experiments, Subject 20, quickly grows out of control and begins attacking and devouring scientists.
The federation marshal, Mike Colby, arrives to investigate the situation and is joined by a doctor named Barbara Glaser. As they explore the research lab, they encounter various mutated and deadly creatures, including a giant rat and a humanoid monster with razor-sharp teeth.
They soon discover that Subject 20 has merged with another experiment, resulting in a highly intelligent and aggressive creature that can adapt and evolve to overcome any obstacle. With time running out and the creature getting stronger by the minute, Colby and Glaser must find a way to destroy it before it escapes the lab and wreaks havoc on the rest of the planet.
As they battle their way through the lab's corridors and fight off various mutant monsters, the duo also begins to uncover a sinister plot involving the lab's director, who may have intentionally allowed the experiments to go out of control in an effort to create a new form of life.
In the film's climactic finale, Colby and Glaser use improvised weapons to take down the monstrous creature in an intense battle that leaves the facility in ruins. The two survivors, battered and bruised but alive, return to their ship and blast off into space, leaving Xarbia and its deadly secrets behind.