This sequel to PROMETHEUS takes place ten years later. A colony ship is on its way to a habitable planet. All two thousand people are asleep except for the synthetic humanoid, Walter (Michael Fassbender). When the ship is affected by an exploding nebula the crew is awakened-and decide to explore a nearby earth-like planet. It's here they find the crashed ship that Elizabeth Shaw and David commandeered in PROMETHEUS. The crew also become contaminated by spores which cause them to develop a form of alien. We learn that David has survived and is, in fact, responsible for slaughtering a city of Prometheans when he arrived. He released the spores on them and ever since has been experimenting with the alien life-form, trying to modify it. This, he does, and it's the creature that we know from the first three ALIEN movies. It's all very interesting-and the confrontation between David and Walter is great (as they are portrayed by the same actor yet have completely different personalities). However, this sort of dismisses the ALIEN vs. PREDATOR movies, which basically take place in our present day-how did these "finished" aliens show up here when they haven't even been genetically modified to their present form for another 150 years? Time travel?
As an ALIEN movie this works well, though it gets a little ridiculous at the end with the ALIEN clinging to the ship. However, it does answer all the questions presented in PROMETHEUS and is a good sequel to that movie.