Aboard the AKI space craft, a space station dedicated to biological research, Laura Lewis is in a deep cryogenic slumber. The jets of the chamber dissipate as the craft's emergency systems are activated. Laura is awakened by a large detonation on her deck. Outside a door marked with the letters E0, something of great strength is trying to break free. The door is thrown down, and the hallway is filled with a bright, incandescent light, followed by a horrific growl. Pipes and the remains of the steel door shift around, as if being stepped on. Laura, unaware of what is happening, uses the video phone located above her sleep chamber to contact one of her crewmates, Parker. Laura watches in confusion as Parker looks away from the monitor, to his room's entryway doors. A screech sends him backing up to reach for his gun. Laura watches as Parker is mutilated by an unseen enemy. Getting dressed and grabbing her gun, Laura heads out to learn what attacked Parker. As she ventures through the ship, Laura's earring-shaped "guidance system" gives her aural warnings of invisible enemies (seen escaping in the intro sequence) roaming the ship's corridors. Laura must fight these enemies, meet up with surviving crew members, and escape the AKI.