The Roughnecks have found a source for oxygen in the creature that they are inside of. Doc and Flores go ahead and find the major source so they can hook up the compressor to send it back to the ship. Rico and Brutto are following but Brutto slips down a shaft and falls. Rico goes down and gets him. Rico is coming back up the shaft when he sees that the hole that Flores and Doc went through is now shut tight. He makes it back up and meets up with Razak, Higgins, and T'Phai. Razak sends him back to with Higgins to find Doc and Flores while he and T'Phai take Brutto back to the ship.
Rico and Higgins get back to the shaft and Rico goes down and finds the tunnel open again. He and Higgins go through and Higgins starts acting weird due to his lack of oxygen. He tells Rico to go on and find them and Rico reluctantly leave Higgins with the compressor.
Razak and T'Phai get Brutto back to the ship and Gossard tells them that Brutto is okay but that he has a couple of broken ribs. Zander is acting strange and is trying to get out of his seat. He keeps saying that the Firefries live to burn. Gossard thinks for a moment and then realizes that the creature that they are in are using the Firefries for fuel. He asks Brutto where the baby Firefries were being hatched and he, Ibanez, and T'phai go out to harvest some to use for fuel in the Zephyr and Razak goes out to find the others.
Doc and Flores have found a source for oxygen but had been sucked into another chamber after getting the compressor going. They have a close call going through another chamber where the valves kept opening and closing. The get through and run into a dead end and are trapped by some of the leeches that start attacking them. Rico is on the other side and hears the commotion and blasts through and uses a flame gun to kill the leeches and rescues Doc and Flores. Just then Razak shows up and they head back to the ship.
Gossard is having a hard time controlling the Firefries in the fuel tank and Zander has gotten out of his seat and is trying to sabatoge the ship. Gossard and T'Phai try and stop him and he starts the self destruct device. He then goes to the door as they are trying to shut it and he wedges a metal bar in it and Razak comes in and they subdue Zander. Gossard gets the Firefries stabilized and T'Phai is instructed by Ibanez to jettison the self destruct device and he does so. Everyone makes it on board and Ibanez flies them out of the giant creature. They make it to space and the creature is determined to catch them and wakes and starts to move. Ibanez kicks in the thrusters and they get some distance between them and the giant creature and the self destruct device that T'Phai had ejected explodes and destroys the giant creature.
We find out the creature has been named an Ice Bug and it would sleep for thousands to millions of years until a fuel source happened to arrive and then it could continue its journey of destruction. The Ice Bug was a planet destroyer and the one they destroyed had targeted our solar system.