This game is one of the best FPS I've played in a long long time, it captures the feel of the environment and bears a close resemblance to the film in some levels. graphics are very good, as is the control system and gun sounds, voice acting etc.
Ai aren't the brightest and are quite slow, but it's just as well, as the enemies are all over the place, rooftops, alleys, behind you, everywhere, RPG's, fixed machine guns,the lot, so you have to be on your toes looking around all the time, some of the ai are fixed and will be in the same place each time you play a level, and then there's the roamers, those that just move around and so you never really know where they are. I found the 16 single player levels varied and fun, and the story moves along at a nice pace,the last mission is a so called fictional mission, I won't spoil it and give it away, but it's a cracker.
If your a fan of the film buy it, if you played the game and enjoyed it, then see the movie, both are excellent!