It starts off like a normal action movie in which the protagonists, leaded by Dutch, goes in guns blazing, killing everyone in their way to retrieve hostages. It's only in the second half of the movie where the science fiction elements takes place and we start to see the alien stalking and killing the group, one by one. It makes for some very intense moments. The suspense heightens and you don't know who is going to get hit next and you feel a hopelessness for the team members (can't blame some of them for losing their minds). The parts where it goes into the alien's point of view, complete with a heat sensitive/infrared view feels somewhat weird and random. I understand where it's coming from but it feels at odds with the rest of the film. The ending was good and it reveals some of the mystery by letting us see the alien's face. A good movie with plenty of exciting moments but somewhat lacking in the alien's backstory.