Who's in It:
The Rock, Karl Urban, Rosamund Pike
The Basics: Marines chase and get chased by monsters in outer space. Seen Aliens? It's like that, only not as good.
What's the Deal? Any career underachiever will tell you that when expectations are low you can really shine. Or at least not utterly fail. Of course, the people who make movies based on video games almost never understand this paradigm (watch the insanely boring House of the Dead for definitive proof, because it's very close to the nadir of suckiness). So the good news here is that this game-to-film adaptation succeeds with lots of very cool killings. Isn't that what you wanted to know?
Gorehound Paradise: You get severed hands, severed heads, severed torsos, a dude who rips off his own ear because the Doom-monsters made him that crazy, another dude who eats live rats, a guy who cuts himself up for God, mutilated animals, baby humanoid skeletons, face-eating Doom-monsters with tongues that have minds of their own and one alien autopsy.
Percentage of Dwayne Johnson vs Percentage of The Rock: OK, you know how when he wants to be all actorly, he'll sometimes go by Dwayne? Like when he's playing a gay bodyguard in Be Cool? This ain't that. This is about him shooting monsters with a really, really big gun. He's a one-man gender-studies course on "masculine performance," that Dwayne.
All-Purpose Political Film: No matter your leanings, you can read this movie as either a rally-the-troops battle cry (like when The Rock shouts, "We kill 'em all!") or as a critique of the military sticking its collective nose where it doesn't belong and suffering the consequences. Everyone's happy.
Shout Out to Gamers: At one point, the movie actually becomes the game and all you see is the big gun at the bottom of the screen picking off monsters left and right.