It is a sad truth that some theatrical trailers, expertly conceived and cut together to make a two-and-a-half-minute promotional reel, far outpace the feature-length films they are advertising. Such is the case with "Legend of the Guardians: The Owls of Ga'Hoole," based on the first three young-adult novels in the expansive fantasy series by Kathryn Lasky. Whereas the trailer for the picture was visually glorious bordering on breathtaking, powerfully encapsulating the majesty of its owl characters and the awesome freedom of soaring through the sky—and emotionally scored, to boot, with the 30 Seconds to Mars track "Kings and Queens"—the movie itself is a relentlessly dour experience with bland heroes, even blander villains, and a plot that is sketchily formed and distinctly uninteresting. Capped off by a pointless, ineffective theatrical 3-D presentation that criminally uglifies the would-be attractive images, the only thing spectacular about "Legend of the Guardians: The Owls of Ga'Hoole" is its sheer lifelessness.

Nestled in their home high among the treetops, owl son Soren (voiced by Jim Sturgess) delights in hearing the adventurous stories his father tells of the guardians of Ga'Hoole, warrior birds trained to protect their kingdom. When he and his more cynical brother Kludd (Ryan Kwanten) get into a scuffle and fall to the forest floor, they are promptly snatched up and taken to the lair of the nefarious Metalbeak (Joel Edgerton) and Nyra (Helen Mirren), out to pluck all the owl races save for the "pure" barn owls. Soren escapes and makes his way to the Great Ga'Hoole Tree, where he prepares to do battle alongside the guardians against Metalbeak's and Nyra's clan. Throwing a wrench in things is Soren's discovery that Kludd has now joined the opposing forces.

Directed by Zack Snyder (2009's "Watchmen"), "Legend of the Guardians: The Owls of Ga'Hoole" is overcome by a pall of lethargy—and, courtesy of the 3-D, a sheath of gloomy, vibrancy-deficient grime—from frame one. The script by John Orloff (2007's "A Mighty Heart") and Emil Stern (2008's "The Life Before Her Eyes") is morose and humorless to the point of being no fun at all. This isn't helped by a severe lag in the pacing department, pulled down further by an overabundance of talky exposition about as titillating as a dry legal document. Too often the film feels the need to tell the viewer what is happening rather than show it, and that's certainly not ideal for a family film. Then again, neither are owls being slaughtered, but that's here, too.

As impressively life-like as the computer animation often is, the owl designs are a critical hindrance. Simply put, too many of the characters look exactly alike. Figuring out who is who is fruitless, though, since they're all about equal in their lack of personalities and distinguishing factors. The battle sequences aren't involving and they don't give us a reason to care. Most of them boil down to a lot of feathers flying and random thrashing about. On occasion, there appears to be mists of blood spraying from wounds, but one can't be too sure since the 3-D dims the brightness level to the point where most everything looks to be a shade of brown or black. Shots of these same scenes in the 2-D trailer, it should be noted, look colorful and exquisitely detailed.

When, midway through, an up-tempo pop song ("To the Sky" by Owl City) is shoehorned into a montage, it's jarring. The song is pretty good, but it's far too peppy to fit in the midst of such a hushed, deadly serious tone. The only reason it's been included is because the powers that be thought it would be cute for a music group called Owl City to create the music for a movie about owls. In this moment, it became crystal clear: the promotional team and possibly the filmmakers (you can never be too sure) were too busy thinking of gimmicky ways to increase merchandising sales to actually make something worthwhile and creatively valid. For a film about the nobility of owls, that's an awfully mixed message. On second thought, nowhere does the movie state humans are noble.

Unsubtly stealing from "Star Wars" (the repeated guidance to "trust your gizzard" is simply a variation on "may the force be with you," while a treehouse community looks so familiar one half-expects the owls to be co-existing with Ewoks), "Legend of the Guardians: The Owls of Ga'Hoole" is a grim, emotionally icy effort from a director whose last two films, 2007's "300" and the aforementioned "Watchmen," were also grim, emotionally icy efforts. Those were targeting adult audiences, however, while this one is going after kids. Younger tots will likely be scared. Older kids, if undiscriminating, will be bored but might think the incomprehensible chaos of the action scenes is okay. Nobody will walk away having learned or felt anything other than, possibly, that they wish they didn't have to pay premium ticket prices in exchange for wearing sunglasses inside a theater and watching a screen with subpar picture quality. The movie's visuals might have been the one strength in a sea of negatives (and they no doubt will be when it comes to Blu-Ray in high-definition), but in 3-D not even those are worth a look. For a film that looked so very promising in its previews, "Legend of the Guardians: The Owls of Ga'Hoole" is easily one of the year's most disappointing releases.