Rookie troopers Rico, Flores and Jenkins journey to Pluto as part of Alpha Team "Razak's Roughnecks" on what is supposed to be a simple mop-up operation, but find a major threat to the research stations from plasma-shooting alien Bugs.

When the Roughnecks pick up a distress call from pilots Ibanez and Barcalow, who are under attack at a research outpost, Rico risks the safety of his own squad to save Carmen.

The squad is assigned to assist intelligence officer Earle Walker in capturing a live Plasma Bug and bringing it back through enemy territory.

Rico has to train Higgins the reporter to defend himself in combat, as the Roughnecks try to defend themselves from new flying Bugs that seem impervious to laser fire.

When the Roughnecks go beneath the surface of Pluto to locate the Bug army's incubation center, Flores suffers from disabling claustrophobia.