Long ago, in the early days of digital 3D—we're talking aught-aught-nine here, maybe aught-aught-eight—the inimitable Brendan Fraser starred in Journey to the Center of the Earth 3D, a Jules Verne-inspired romp that featured the charming Mr. Fraser tumbling into a hole alongside his slightly less charming son. Landing in a fantastical world of giant mushrooms and phosphorescent CG bullshit, Mr. Fraser bonded with his son as they built a raft, jumped on floating rocks, and fought a tyrannosaur. Also, because the film was in 3D, a whole bunch of dumb crap was always flying at the camera.

The 3D in Sanctum is less garish than that—I'm guessing producer James Cameron was kind enough to tell Sanctum's director, Alister Grierson, that not every single thing onscreen needs to be lewdly thrust into viewers' faces—but in every other capacity, Mr. Fraser's dorky Journey kicks Sanctum's ass. Like Journey, Sanctum's a father/son flick that takes place underground; here, ostensible expert caver/diver Frank McGuire (Richard Roxburgh) leads an expedition that includes his estranged 17-year-old son, Josh (Rhys Wakefield), and a jackassy financier, Carl (Ioan Gruffudd, jackassy as ever). They're climbing and diving through a massive cave system in the South Pacific when a cyclone floods the caves, inspiring every member of Sanctum's thoroughly unlikeable cast to start diving, climbing, weeping, maiming, and murdering their way back to the surface.

Sanctum's opening claims it's "inspired" by a true story, but I call bullshit—whatever nugget of truth might be in this thing is buried by obnoxious characters and dumbass plot twists, or drowned out by dialogue shouted in a relentless monotone. ("You heartless bastard. Have you no decency.") By the time Frank and Josh bond by reciting Coleridge's Kubla Khan while climbing up a narrow rock chimney slathered in batshit, the 177-years-dead Coleridge is far more interesting than anyone in this stupid cave.

Speaking of stupid: In the category of "Stupid people doing stupid things," 127 Hours hacks right through this thing; in the category of "stressful shit happening underwater," Cameron's The Abyss offers significantly more watery thrills; in just about every other category—including but not limited to subterranean tyrannosaurs—I again refer you to Mr. Fraser's Journey to the Center of the Earth. But as long as I'm making too-easy sport of how terribly Sanctum stacks up against... well, anything, I'd be remiss not to mention Neil Marshall's 2005 horror flick The Descent, another "stupid people doing stupid things" film that nonetheless eked out creepy, claustrophobic terror from its rock-hewn confines. And since The Descent didn't even pretend to be authentic, Marshall got to spice up his spelunking-gone-awry tale with albino mutants! Sanctum could use a lot of things, but perhaps nothing more than one of The Descent's screeching, batlike freaks, happily gnawing on one of Ioan Gruffudd's useless femurs.