Two astronauts awaken in a hyper-sleep chamber aboard a seemingly abandoned spacecraft. It's pitch black, they are disoriented, and the only sound is a low rumble and creak from the belly of the spacecraft. They can't remember anything - who are they, what is their mission? The only way out of the chamber is a dark and narrow airshaft. Corporal Bower, the younger of the two, crawls inside, while the other, Lt. Payton, stays behind for guidance on a radio transmitter. As Bower ventures deeper and deeper into the ship, he begins to uncover a terrifying reality. Slowly the spacecraft's shocking and deadly secrets come unraveled, and the astronauts realize that the survival of mankind hinges on their actions.