Visionary in compartmentalized spurts but otherwise just another tepid spaceship-set creature feature, "Pandorum" starts and ends with a promise the middle seventy-five minutes are lacking. The director is Christian Alvart, whose previous film, the Renee Zellweger thriller "Case 39," has been sitting on the shelf for nearly three years. That may sound like a sign of trouble to come, but Alvart actually does a fair enough job at the onset of carefully building tension through measured pacing and a sound design unafraid of silence. Unfortunately, that all goes out the window with the introduction of superfluous supporting characters and a race of villains who, with their leather, spikes and face paint, look like the same albino goths who previously starred in 2001's "Ghosts of Mars." The second these misguided baddies show up, the film's claustrophobic mood all but completely dissipates.

In the year 2174, Earth has become uninhabitable and the giant spacecraft Elysium has set out to begin colonizing Tanis, the only other planet able to sustain human life. Corporal Bower (Ben Foster) and Lieutenant Payton (Dennis Quaid) awake from extended hypersleep with no memory of where they are or what their mission is. As their pasts gradually drift back into focus, Bower makes his way through the dark bowels and dank tunnels of the ship, moving ever closer to the main control room where he hopes to reset the reactor and continue their journey to Tanis. Also onboard, it quickly turns out: something that may very well not be human.

"Pandorum" probably does not sound like an example of shining originality, and that is because, up until the final minutes, it isn't. Still, there is some initial intrigue in the power of the unknown. The first act, with Bower and Payton all alone trying to regain their memories, capably draws the viewer in. Bower's subsequent journey through a maze of airshafts, rubber tubes like tentacles lining the walls, is equipped with a similar sense of constriction and doom as 2006's "The Descent." As is often the case, however, the act of dreading what is to come is far more satisfying than the reality.

From this point, the movie makes a series of mistakes that lessen the effect. A few fellow crew members with memory loss, like the mistrusting Nadia (Antje Traue) and the affably foreign-tongued Manh (Cung Le), show up, proving to be annoying rather than good company. The handling of the sole African American character, Leland (Eddie Rouse), comes off as almost racist in his initial role as a wacky, exposition-spouting "magical negro," then goes one worse when he becomes the antagonist, then goes one worse when he segues into a tag-along buffoon, and finally hits his low when he is killed off without having served an ounce of purpose. Even more calamitous than these two-dimensional figures are the, for lack of a better word that would give away a major plot point, monsters. Simply put, they aren't scary. Their design is tacky, for one, and they are shot most of the time using an out-of-the-place shaky-cam and garbled editing that make them even less imposing.

From HBO's "Six Feet Under" to 2005's "Hostage" to 2007's "30 Days of Night," Ben Foster has made a career in recent years out of playing oddballs and bad guys. Though his role as Bower is more conventional, it is nice to see him get to play a relatively normal character this time around. By comparison, Dennis Quaid (2009's "G.I. Joe: The Rise of Cobra") is typecast as Payton, barking orders and altogether sounding authoritative. Cam Gigandet (2009's "The Unborn") is chilling in a limited part as Gallo, a fellow crew member who pops up to keep Payton company and starts acting mighty suspicious.

Watching "Pandorum" play out in an awfully rudimentary fashion does not prepare the viewer for a few third-act surprises. One of them involving Payton and Gallo feels old-hat, not far off from producer Paul W.S. Anderson's own 1997 space-set horror pic "Event Horizon," but the film's last handful of minutes are superb, even wondrous, in their game-changing ways and ultimate wrap-up. "Pandorum," the title describing the process of losing one's mind due to psychological trauma and desolation, ends on a high plateau, but it comes too late to save what has gone before. The stereotypical characterizations and unsuccessful frights are bad enough, but by the time one of the creatures tosses Manh a pipe and they proceed to martial arts fight, it's safe to presume that a shark has been jumped and there is no turning things around.