The first decent use of the Alien and Predator licenses in a video game.
Set in 2154 (twenty years after Aliens and Alien 3 according to the game) AvP is split into three campaigns with one for each species represented in the game. Unfortunately the campaigns don't really feature any actual story; instead they only serve to provide an atmospheric blood bath for the player to participate in.
The first of the campaigns is the Alien campaign; as a newly created Alien your goal is to reunite with and free your abducted hive while securing a ride to Earth carrying with you live eggs. As expected the story is nothing special; the real joy of the Alien campaign comes out of being the movie monster that sends all of the humans running before delivering them to a rather gory end. This is executed quite well as the Alien is fast, and its attacks essentially one hit kill all human characters. The climbing ability of the alien is somewhat flawed, though; sometimes when climbing over corners I found myself stuck. Regardless the Alien campaign gets the "movie monster" feel just right.
The second of the campaigns is the Colonial Marine one. The Marine campaign is essentially a survival story. Alone against an insurmountable number of Aliens you have to make your way through numerous infested installations while being hounded at every turn. This is easier said than done as ammo is scarce, and the Alien spawns are usually infinite so you have to be observant and efficient. Unfortunately when it comes down to it; the Marine campaign is just "another shooter" as there's nothing really separating it from a game like Doom. Sure it's probably the most "terrifying" of the campaigns, but at the same time it's also the most generic.
The final campaign is the Predator campaign. The Predator is essentially the movie Slasher campaign; using your high tech equipment you basically run around killing humans (and sometimes aliens). This can be fun for a while, but it quickly becomes boring when you realize that you don't even need to use your cloaking device since neither the humans nor aliens really stand a chance against you in the first place. The Predator campaign is essentially just the marine campaign with more high tech gadgets, and this is disappointing since the Predator is supposed to be an intergalactic big game hunter.
One common problem in all of the campaigns is that they are really short. The Alien campaign is only five missions long while the Marine and Predator campaigns are only six missions long (and the sixth missions are just final boss battles). Rebellion tried to compensate for this with "bonus missions", each race has a few extra bonus missions that are unlocked after finishing the primary campaign on a certain difficulty. You get the first two after finishing the game on training, the second two by completing it on realistic, and the final one by completing it on director's cut. The bonus missions aren't really an expansion of the primary campaign; just separate "side stories" told through the eyes of other aliens, marines, and predators using the same maps from the original campaigns with some twists. For example, the Tyrargo bonus mission for the alien reveals how the ship became infested. The bonus missions are nice in a way as they add onto the campaigns, but at the same time they simply feel tacked on as they don't really contribute much of anything to the core campaigns.
Visually AvP was great for its time. There was light glare, fairly realistic looking water effects, and human characters had facial expressions. Unfortunately there was no height differentiations. Humans, aliens and predators were all the same height in other words. In a way this made the aliens and predators seem less intimidating as they were no taller than your average everyday human.
From an audio standpoint AvP was fairly average. There was no voice acting (although there was actual acting in FMVs displayed on monitors); the sound effects were pretty run of the mill although they were at least authentic Alien sound effects: IE the motion detector sounded like the motion detector from the Alien films. The music was okay for the setting, but it wasn't particularly memorable.
Aliens Versus Predator is a little rough around the edges due to its brief length and somewhat out of character Predator campaign, but it's still a good example of a movie video game that really isn't that bad.
+ Alien campaign makes you feel like the movie monster
+ Marine campaign can be tense at times
+ Bonus missions improve the games otherwise brief length
+ Challenging without going too overboard most of the time
- Predator campaign doesn't really make you feel like a Predator
- No actual storyline