The Roughnecks find themselves on a large asteroid after their craft, the Zephyr, crashes. Troopers Carmen, Rico, Flores, T'Phai, and company then set out to find a powerful toxin that could be their savior in their battle with the giant bugs that threaten to take over the universe. However, when an investigation leads them to the discovery that the asteroid is infested with the hideous creatures, the Roughnecks' chances for survival begin to look smaller and smaller.