THE SHALLOWS: 2 STARS

Former "Gossip Girl" actor Blake Lively not only stars in "The Shallows," she appears in virtually every frame of the film.

As a woman surfing alone off an isolated island, she is attacked by a Great White shark and must use her wits to get to safety. Vanity Fair dubbed it, "Lively or Death." The screenplay appeared on the 2014 Blacklist, the annual list of the "most liked" unmade scripts in Hollywood, and has been described as "Jaws" meets "127 Hours," but the woman vs. nature struggle sounds more like Blake's "Castaway" to me.

Lively is Nancy Adams, a medical school drop-out spending an idyllic day hanging ten on a secret Mexican beach recommended to her by her late mom.

"What did you say the name of this place was?" she asks a local.

"This is paradise," he coos.

Beautiful and remote, it seems perfect for a restful and relaxing day, but trouble soon comes to paradise when she is stranded on a rock two hundred feet from shore.

As an experienced surfer Nancy should be able to make it back to the beach easily. Unfortunately there is a toothy, bloodthirsty Great White shark looming between her and safety.

"I'm not dying here," she grunts while forming a plan to avoid becoming shark bait.

The Great White in "The Shallows" makes the shark in "Jaws" seem laid-back. Seemingly inexhaustible in his hunt for humanoid tartar, he is a constant menace to the lithe Lively. It's one long nautical nightmare for Nancy as she plots to outsmart and outswim her finned tormenter.

Cinematically it's not as much of a nightmare. The setup is minimal, and as far as actual thrills go, less isn't more in this case. Less is actually less. There are some moments of tension - Spielberg trained us that any underwater shot pointed up at a swimmer or surfer means impending doom - but too much of the film involves Nancy and her seagull sidekick marooned on the rock.

Director Jaume Collet-Serra occasionally embraces the film's b-movie ascetic - he actually has the shark go airborne in one spectacular attack - but mostly he's willing to treat the look of the film like a "Sports Illustrated" layout with vengeful sharks.

He does use some effective tricks - we don't see much of the shark until late into the film and one grizzly scene spares us the bloody details by focussing on Lively's horrified face rather than the action - but the Nature v Nancy storyline isn't amped up enough to for us to care if she becomes fish food or not.