This game very nicely extrapolates some great gameplay ideas from elements in the original movie, but it is too frustrating and drab to really enjoy.
It's a nice genre-buster that could be compared to D2, Half-Life, and some of the general mishmash of third-person shooters. What sets The Thing apart is the interaction with squad mates and the concept of trust - there's often no telling when they might turn into an infected freak and they suspect the same from you.
Unfortunately, many of these transformations are scripted and the best you can hope for in your squad mates is not to set them on fire or get hit by them with an ill-timed shotgun blast to the back.
You'll have to repeat several sequences many times to move on, (but don't expect to be able to save your game at the beginning of a level - if you want to power down and return later, you'll need to find a save point) and it's quite possible that you'll save yourself into a corner by leaving too few resources to get through the next challenge.
I really would like to give this game more praise but it is mostly poor execution of some great ideas.