It is the year 2066 and U.S.S. Santee orbits the Alpha Centauri solar system. the mission, run by Commander Bakewell, receives an urgent SOS from planet AC9. Raptors have attacked and it is up to Captain Mace Carter and his team to restore safety to the galaxy. Ravaged by the deadly animals, Carter and his crew find the planet under extreme warfare and take cover in the only place they can find, a medieval castle amid the ruins. Running out of food and ammo, their ranks are decimated one by one as they struggle to stay alive and discover the secret of the aliens.