Thrilling in 3-D

James Cameron’s name is attached to “Sanctum,” although he did not direct the picture and his name isn’t listed among the writers. He does admit to being an executive producer, whatever that mysterious title might mean.

Take a closer look, and the tell-tale signs are there. For on

e thing, 3-D. The “Avatar” man is all over that. And the dialogue? It clanks and clunks in the weirdly toneless wise-cracky way we remember from previous Cameron outings.

And then there’s all the underwater stuff, practically an obsession for the “Titanic” filmmaker. Yep, this thing just feels like Cameron.

But this time the King of the World has limited himself to a small system of caves in Australia. Co-writer Andrew Wight based the story on an actual experience he had with an emergency in an underwater cave, but I’m going to guess it had almost no similarity to the highly melodramatic sequence of events that plays out in “Sanctum.”

A brash troupe of “cavers” is exploring a complicated and unexplored underground labyrinth when a typhoon hits the area, threatening to flood the camp. All they can do is dive down into the cave and hope to swim their way out to the sea.

They’ve got some high-tech equipment, because the expedition is funded by a billionaire (Ioan Gruffudd, of “Fantastic Four” fame), who has his gung-ho girlfriend (Alice Parkinson) along. But they’re going to have to take orders from the gruff caver-in-charge (leathery Aussie Richard Roxburgh), who knows caves but doesn’t know people. Including his son (Rhys Wakefield) who, of course, is here for this life-or-death adventure.

Mostly death, as it turns out. “Sanctum” is pretty brutal on its cast of characters, who tumble through flooded chutes, get the bends and run out of oxygen at the most inopportune times.

I would like to stand back and mock this over-heated movie, but darned if it isn’t frequently effective. Cameron & Co. are in touch with the prototypical 15-year-old popcorn-munching moviegoer, and the series of whiz-bang escapes and cornball conversations are hard to resist on that level.

This isn’t one of those half-baked retro-fitted 3-D releases. Cameron goes whole hog on this stuff, so the 3-D is by turns thrilling, distracting and just sort of there. If you’re going to use 3-D on something, it might as well be on a crazed adventure movie like this.

“Sanctum” ½

James Cameron produced this 3-D descent into a series of underwater caves in Australia, where a team of explorers gets inundated by a sudden typhoon. Cornball melodrama and clunky dialogue notwithstanding, this claustrophobic affair delivers a few actual popcorn thrills.

Rated: R for violence, language.

Showing: Alderwood Mall, Cinebarre, Everett Stadium, Marysville, Monroe, Stanwood, Meridian, Thornton Place, Woodinville, Cascade Mall and Oak Harbor.