 After killing herself to prevent the government from taking the monstrous Alien to Earth, Ellen Ripley awakens 200 years later to find she has been cloned in order to withdraw the Alien living inside her. As the world around her begins to fall apart and the terror begins again, Ripley realises that the scientists who cloned her may not have fully removed the Alien from her, at the same time that she is, once again, perhaps the only one who can stop the horrific infestation from reaching Earth...