Something has gone terribly wrong here. For some reason, the makers of Doom, a sci-fi action flick based on the mega-selling video game of the same name, believed that the source material demanded to be taken seriously. This logic might have made sense if the movie was based on a Shakespearean play or a beloved best-selling novel, but c'mon-we're talking about a bunch of pixels. And it's not like the original game featured an elaborate plot a la the Metal Gear Solid series or iconic characters like those troublemaking Mario Brothers. Doom's primary appeal has always been its simplicity; the nameless hero marches through an endless series of corridors blowing away armies of gruesome monsters with a really big gun. This premise should have been a snap for Hollywood to crack, but it's taken over a decade for Doom to reach the big screen. And now that it's here, it already feels like yesterday's news, as the modest opening-weekend grosses attest. So what went wrong? Simply put, the filmmakers produced a mindless action movie that isn't mindless enough.

Boldly stealing from Aliens, Stargate and virtually every other sci-fi blockbuster made in the past 20 years, Doom deposits us on a vaguely futuristic Earth where mankind has discovered an express passageway to Mars known as The Ark. This portal paved the way for the construction of a research facility on the Red Planet, where scientists play around with human genetics far away from the prying eyes of the government. Of course, that kind of research never turns out well and, as the movie begins, a group of men and women in white coats are running frantically from a monster of their own creation. Eight combat-hardened Marines, who sport colorful nicknames like Destroyer and Goat, are immediately dispatched to Mars to investigate the situation. Led by the no-nonsense Sarge (The Rock), the squad finds the research station overrun with super-strong creatures. One of the only people left alive is a pretty scientist named Samantha Grimm (Rosamund Pike), whose brother John (Karl Urban) just happens to be Sarge's right-hand man. Dr. Grimm brings the team up to speed on what exactly is going on. It seems that Mars' previous inhabitants-the same ones who built The Ark-possessed a 24th chromosome and her fellow scientists got the bright idea to inject it into human subjects. The results of this ill-fated experiment are currently running rampant through the station. Now the Marines have to use all the considerable firepower at their disposal to destroy these creatures before any of them find their way to Earth.

The film's early scenes play exactly like the introduction to a videogame; you meet the characters, receive your weapons and mission objectives and enter the arena where the action will be taking place. Once all these details are in place, all that's left is to start the carnage. But Doom takes a remarkably long time to get to the fun stuff. The exposition drags endlessly on as screenwriters David Callaham and Wesley Strick keep introducing unnecessary plot points that clutter up the narrative. For example, there's a pointless subplot involving Samantha and John's parents, who were two of the first scientists on Mars and died in a tragic accident while their kids were still young. The business with the 24th chromosome is ludicrous as well, but the film commits the fatal mistake of trying to make it believable. This leads to long scenes of Dr. Grimm lecturing the Marines about the hows and whys of the fake science even though they-like the audience-don't really care. (It doesn't help that ex-Bond girl Pike gives a resoundingly terrible performance.)

Unfortunately, the movie doesn't even improve once the bullets finally start flying. The action sequences are disappointingly pedestrian, not to mention severely underlit (all the better to hide the cheap makeup and CGI effects, no doubt). There's no sense of fun to the proceedings; even The Rock, who has demonstrated his comedic chops several times before, isn't allowed to crack a smile or cock one of his famous eyebrows. As for the heavily promoted "first-person shooter" sequence-which replicates the point-of-view seen in the game-it only serves to remind you how much more entertaining Doom is when you're the participant rather than the spectator.

-Ethan Alter