Based on a popular series of children's books by Holly Black and illustrator Tony DiTerlizzi, "The Spiderwick Chronicles" is a serviceable, somewhat down-market entry in Hollywood's ongoing fantasy film sweepstakes. While it doesn't have the bloat and jumble of last year's disastrous "The Golden Compass," it's also lacking in the distinctiveness that makes its competitors stand out from the pack. The allegorical heft of "The Lord of the Rings," the scintillating Anglo-mania of "The Chronicles of Narnia," the endless convolutions and contrivances of the Harry Potter franchise -- none of these qualities has a counterpart in "The Spiderwick Chronicles," at least as it has been transferred to the screen.
In spite of a thin patina of wizardly erudition and prefab myth-making, what the new film banks on is a series of kinetically frenzied, computer-generated tussles and chases, loosely tied together with a tidily handled plot. There's not much to inspire, but from a parent's point of view, a welcome selling point is that if you skip the previews and the credits, you can be in and out of the theater in 90 minutes.
Things get off to a rather dispiriting start, as we're introduced to the Grace family, an unquiet clan in the process of falling to pieces. Compelled by circumstance to abandon their New York City home and seek refuge in the dilapidated country house of a recently committed spinster aunt, the Graces (Dad markedly absent) snipe and lash out at one another sourly. Mom (Mary-Louise Parker) is powerless to control her hotheaded preteen Jared (Freddie Highmore) even with the support of his mild twin, Simon (Highmore again), or their older sister, Mallory (Sarah Bolger), a budding Amazon who seems to be tirelessly training for a spot on the Olympic fencing team.
Grumpily ensconced in his new surroundings, Jared stumbles upon the house's magical secret: "Field Guide to the Fantastical World Around You," a passport to the unseen world of the faeries sporting and marauding in our midst. The life's work of Jared's great-great-uncle Arthur Spiderwick (David Strathairn), the "Field Guide" is guarded by an elfin brownie, Thimbletack (voiced by Martin Short), and sought after by arch-ogre Mulgarath (Nick Nolte), who, armed with its secrets, would establish perpetual dominion over faerie and human alike. Soon all the Grace children (don't bother looking for theological significance in their suggestive surname) are embroiled in the world-altering struggle to keep the Ring uh, that is, the "Field Guide" from the evil clutches of Voldemort or, rather, Mulgarath.
This summary might make you worry you will soon have to commit the movers and shakers of yet another drearily complex fantasy world to memory, but fear not. "The Spiderwick Chronicles" takes for granted that we've read our Tolkien, our Lewis, our Rowling, and it lightheartedly cobbles their elements together without asking to be taken too seriously. And although the stakes in the film are high, much of the dialogue is aggressively twee, especially where the adorable Thimbletack or Hogsqueal (voiced by Seth Rogen), a gluttonous, good-hearted hobgoblin, are concerned.
While its willingness not to tarry over details lets the film skip along briskly, it does so at a cost. There can be poetry in the sort of arcane knowledge that's said to be in the "Field Guide," but this film keeps Arthur Spiderwick's lore to itself. One has to scan the film's official Web site to learn that the goblins bedeviling the Graces have some sort of link to the Revolutionary War, or that the sprites delicate, airborne flowers with faces actually steal the petals that adorn them from unsuspecting gardeners. But the kind of charm lent by such whimsy goes mostly uncultivated here.
Instead, the film concentrates on the more raucous amusement afforded by rampaging trolls, intercontinental griffins and toadlike monsters who can be dispatched with a mixture of tomato sauce and vinegar. The game dual performance by Freddie Highmore doesn't distract from the special effects at the movie's core. The proceedings also get a boost from a wistful Strathairn and the formidable Joan Plowright, in the role of Spiderwick's aged daughter. It all goes down smoothly enough, but it's as insubstantial as a vaguely remembered dream. (PG) 98 min. S