Returning from a combat mission in a retrieval ship, the Zephyr, the Roughnecks are re-routed to an asteroid to join scientists from another ship, the Sequoia, in a quest for a bio-weapon against the bugs. Just as they are coming in for a landing, tiny flame-breathing bugs, Firefries, hatch from Zander's skin. The ship crashes, badly damaged, but there are no serious injuries. Teams are sent out to locate the Sequoia. One team, Razak and Doc, falls into a subterranean network where they are attacked by marshmallow-like Leeches. Another team, Brutto and T'Phai, find themselves in a battle with adult, human-sized Firefries. Razak and Doc, joined by Dizzy and Gossard from the ship, join in this battle. Meanwhile, the third team, Carmen and Rico, is buried by an avalanche, and beneath the snow they share some intimate moments. Dizzy saves them. All return to the Zephyr, where Higgins awaits with the recovering Zander. They finally realize that they're on the wrong asteroid; the Sequoia awa
