In a retcon of the series' cliffhanger,
Alien Nation: Dark Horizon begins with Susan Francisco and her daughter Emily falling victim to a newly developed viral infection that was created by a group of human Purists to exterminate the
Newcomer species. There is also a new sub-plot running parallel to this one, the story of Ahpossno, a
Tenctonese Overseer who lands on Earth to find any surviving Tenctonese and bring them back into slavery. The idea of a signal sent into space by the surviving Overseers was explored in the
Alien Nation episode "Contact". The series finale episode "Green Eyes" ended with contaminated flowers being delivered to the Francisco family and Cathy informing Matt that they have been hospitalized.
Dark Horizon re-stages these events so that George Francisco is not present and also presents a slightly different version of Cathy's arrival at Matt's apartment. Eventually Ahpossno comes round to the freedom enjoyed by the Newcomers on Earth but has already alerted his superiors to their presence. In an act of self-sacrifice he is poisoned by the tainted flowers and uses his scout ship to return to the approaching Overseer mothership. With his dying breath he declares that all the Newcomers are dead - a result of the Earth's atmosphere being toxic to them. One of the Overseer supervisors smells the flower he has brought back with him and reacts to it, confirming his story. ==Cast==