The Shallows is Jaws for millennials, brought to you by Sony, says CBC's Eli Glasner

The Shallows is a film with few illusions — it knows what you want: a beach, a shark and Blake Lively in a bikini.

But before it can deliver the goods, we'll need to wade through a half an hour of prologue.

Lively plays Nancy. She's sad after her mother died, which is why she's travelled to Mexico — to visit Mom's favourite beach.

Data plans be damned, Nancy videochats with her sister in Texas, only to be interrupted by dad delivering more backstory: after Mom died of cancer, Nancy dropped out of med school and went into vagabond mode.  

So, with her friend back at the hotel, the intrepid Nancy paddles into the surf. Let the games begin. 

Spanish director Jaume Collet-Serra has shown an expressionist flair for horror and churns our fear with underwater shots that linger, as the predator stalks its prey. Unlike John William's classic score for Jaws, composer Marco Beltrami's work on The Shallows grinds and swells as the inevitable encounter approaches. It's like a soggy version of Inception's score. 

When beauty and beast do meet for the first time, it's a terrifying moment that leaves Nancy clawing at the water in a red haze of pain.

Then, The Shallows shifts into survival mode, treading in territory similar to The Grey or Open Water. With a bleeding gash across her thigh, Nancy is stranded on small rocky island with the shore some 200 yards away. Between her and the beach, though, is a massive great white in a feeding frenzy for humans.

MacGyver in a wetsuit

While Collet-Serra's camera hugs his photogenic star's curves, what The Shallows offers Lively is a chance to get beneath the surface and share some of the same grit she exhibited in The Town. However, the problem is the material, which vacillates between primal and puff piece. 

The film works best when it embraces the sheer physicality of Nancy's predicament — and I'm not referring to her orange Creamsicle-coloured bikini. With only a wounded seagull for company, the med school dropout transforms into MacGyver in a wetsuit, tracking her opponent's patterns and manufacturing tools from the clothes off her back. 

But where Open Water embraced the inescapable dread of the situation, The Shallows intercuts action with weepy monologues and blatant product placement, complete with jarring screenshots that clash with the elemental nature of the story. It's Jaws for millennials, brought to you by Sony Mobile.

As the tide rises and the final confrontation looms, Nancy's ability to endure goes from impressive to truly heroic, but by this point most of us will be past the point of minding.

In the end, the aptly-named film delivers a brisk and highly polished package of summer scares that suggests Lively could rise to the occasion if provided material with greater depth. 

RATING: 3 out of 5 stars