After the attempt to establish a colony at Proxima Centauri ends in disaster, humanity attempts to establish a colony at Trappist, the next closest habitable star system, 80 light years away from Earth.

An advanced team aboard the scout ship Exo-1 is shocked when they discover traces of a vanished civilization, the Marzon. Not only do they find ruins of the Marzon aliens, but they discover this people were exterminated by another alien race. This mysterious race has left behind robots to defend the planets. While Exo-1?s crew believes it can secure the planet against these robotic defenders, it?s less certain it can defend itself if the robot?s creators return and plan to colonize.. Can they avert another disaster?