Unconscious, unaware, Ripley is the last human survivor of the Nostromo, her shuttle lost in deep space. Meanwhile, the crew aboard the mining ship Marion, faces a catastrophic collision with one of its own dropships and has to contend with the alien infestation on board.

Marooned in a decaying orbit above the planetoid LV-178, the crew struggle to tackle the threat at hand, when an unexpected visitor makes her presence known.

Ripley’s shuttle has docked with the Marion. She arrives traumatised, only to find her rescuers under attack by a familiar foe. To make matters worse, it seems that Ash, an android she’d thought killed aboard the Nostromo, has uploaded his AI routines into her shuttle’s computer.

Outside, the ship’s orbit is decaying faster than expected. The crew has just days to escape before they burn up in LV-178’s atmosphere.

Ripley and the crew aboard the Marion are running out of options to escape certain death. Their orbit is decaying rapidly. With only a few days to decide, they settle on a plan. If they can deal with the alien infestation on board the Samson, their remaining undamaged dropship, they may be able to return to LV-178’s mining installation and retrieve the vital fuel they need to escape on Ripley’s shuttle.

Ripley finds herself reliving the worst of her nightmares as the crew attempts to both evade and hunt the alien intruders. Further complications reveal themselves as we find that the new stowaway may not be as unwelcome as first appeared. The crew, armed and on edge, board the Samson. What awaits them, they can only imagine....

The crew finally arrives at the deserted trimonite mine on LV-178. Cautiously, they make their way through the facility to salvage the spare fuel cells they desperately need. Ripley and the Marion crew find themselves facing an infestation of aliens. All the while, Ash, is keeping a remote eye on their progress. What is his real agenda and who will survive?

As the team’s options dwindle, it begins to dawn on them that there may be larger forces at work, manipulating them. On exploring a derelict ship, yet more terrifying adversaries threaten their very existence, before the surviving crew members stumble upon a chamber filled with unborn aliens.

The crew’s chances of survival have never been more precarious. Further exploration reveals dozens of un-hatched queens. Behind the scenes, Ash is tracking down Ripley’s daughter, gaining valuable leverage for his own mission. Ripley is badly injured and it seems that the aliens have a nose for fresh blood.

The heavily wounded and depleted team finally escapes and reaches their dropship, only to face another dilemma. Sneddon, who has been attacked by a face-hugger during their encounters in the mine, appears to recover from the alien’s attack.

It falls to Ripley to point out the truth that nobody wants to face. They either abandon Sneddon at the mine or risk the birth of a new alien aboard their ship. It’s a choice no-one wants to consider and a decision no-one should have to make.