They first lost me in this movie when the scientist takes off his helmet in an alien environment despite the protests of other scientists. No real scientist would ever do this and the movie became a cartoon at that point. Immediate loss of suspension of disbelief. It got worse though. It never explains why the android poisons the guy. The engineer whose job was supposed to be tracking their location gets lost on the way back to the ship, and then the scientist he's with starts playing with an unknown alien life form because it's "so cute." Of course it kills him. This was probably the most preposterous moment of many in the movie. It never really explains why the one guy morphs into a some kind of zombie spider-human and attacks people at the ship. It never has any comment from the alien (who has identical human dna but doesn't look identical to humans) as to why he attacks the people at the end. The girl wants to fly to the alien world at the end rather than go home because she has to know why they created us and now hate us. Duh, there's going to be more than one faction of these guys in the sequel.

Tremendously disappointing movie coming from the director who made the incredible classic first Alien movie.