Jaume Collet-Serra‘s The Shallows is relatively inoffensive for the first…what, 25 minutes? Lulling, I mean. A tropical Mexican (actually Australian) surfside setting. Brief glimpses of Blake Lively‘s tanned bikini bod. A tranquil, crescent-shaped cove under radiant blue skies. Hefty surfer swells rolling in.

And then the dumb shark tale begins, and it gradually gets harder and harder to accept. The big ending, trust me, is ludicrous. But it’s a fairly lightweight, see-it-and-forget-about-it thing. I didn’t hate it. I just sat there and smirked. Okay, a single shock cut made me jump but that’s it.

The film pretty much rests on Blake’s shoulders, and to be fair she delivers as well as can be expected. She works it, I mean. Gives her all in conveying the fear, panic and pain. It’s the damn shark I didn’t care for, or more precisely his behavior. This is one determined predator who wants to feed, yes, but his main purpose is to eat Blake Lively. She does what she can to elude and survive, but Sharky-poo won’t quit. “I’m really after you, bikini babe with the Oakland booty…I can’t wait to sink my teeth into your flank!”

SPOILER (as if anyone cares): There’s a ten-minute passage in which Sharky eats two and a half guys and he’s still after Lively. Correct me if I’m wrong but sharks are instinct-driven leviathans who eat when they’re hungry and don’t eat when they’re not. Right? They’re not squirrels. They don’t store up for the winter.

Continuing Sharky thought-balloon: “Wow, that first guy tasted great! I love it when they scream and howl, and then all that blood and bone…yum! The younger victims always taste better, and those internal organs are like strawberry shortcake. And then I grabbed another young guy. Couldn’t believe my luck! And then the legs of a third guy….am I dreaming? Two and half bodies, enough to sustain me for several days if not a week.

“But I still haven’t eaten whatsername and that’s the main thing here. It’s not a matter of hunger or nutrition or instinct. This is a totally personal mission and I want that aching, moaning Texas blonde between my jaws, damn it. And I’ll save the head for last. That’s what the screenwriter (Anthony Jaswinski) and the Columbia executives who developed and financed this movie want me to do, at least. What can I do — argue? I’m a CG creation and I do what they say. Whatever your complaint is, I don’t wanna hear it.”

To summarize, I found The Shallows to be cheap, cloying, unnatural, silly. I still don’t know what happened at the end. And what a doctor Blake turns out to be — stitching her own leg, fixing a dislocated bird wing. (I wrote yesterday about “Steven Seagull.”) It was almost a poor-man’s All Is Lost in a way but saddled with the studio-required necessity to deliver a big climactic mano e mano. And there’s a one-year-later epilogue…forget it.