When Ellen Ripley finally returns to Earth; she learns that the planet LV-426 - now called Acheron - has been colonized. But LV-426 is where Ripley and the crew of the Nostromo found the original Xenomorph - the killing machine known as the Alien. Protected by the Colonial Marines; the colonists seek to terraform the storm-swept planet. Two such residents are Anne and Russell Jorden; seeking a fortune that eluded them on Earth. On Acheron; Anne gives birth to the colony's first newborn. Rebecca Jorden; also known as Newt. The wildcatters discover a vast; decaying spaceship. The horseshoe-shaped vessel is of particular interest to Weyland-Yutani; and may be the answer to their dreams. But what Anne and Russ find on board proves to be the stuff; not of dreams; but of nightmares.