The shark genre doesn’t have a lot of room for innovation (all due respect to my shark novel coming this month). That’s probably been true since Jaws, but it hasn’t stopped filmmakers from putting their own stamp on one of nature’s fiercest predators. I don’t think anyone would ever claim The Shallows breaks new ground–if you’ve seen the trailer, you know exactly what you’re getting into–but that shouldn’t matter. If you’re in the market for a white knuckle thriller that’s gorgeously shot, well acted, and plenty thrilling, look no further because this one checks those boxes with ease.

Blake Lively is a young medical student who makes a pilgrimage to a secluded beach in order to work through some personal issues. She’s come to surf these waters because her late mother had done the same in her youth, and this vacation is supposed to signal the ultimate rite of passage. She stumbles upon a floating whale carcass and catches the attention of the predatory great white that killed it. Sensing more prey close by, the shark isn’t about to let her get back to land.

Director Jaume Collet-Serra understands this kind of movie works best at a brisk pace. At 87 minutes, there’s not a lot of filler, although I think it could’ve worked even better had been just a little tighter. Still, The Shallows is lean, mean, and refreshingly devoid of bloat. We get little pieces of Lively’s past scattered throughout, but only the essentials. Instead, Serra knows what we’ve come for and tightens the screws as soon as the movie starts.

Shot in Queensland, Australia, Serra takes us there through gorgeous use of widescreen and a confident understanding of suspense. The man vs. nature subgenre has been mined pretty well over the last fifteen yeras, with films like Open Water and The Canyon unafraid to let nature triumph over ill-fated protagonists. Because of this, we’re never really sure which way The Shallows will go, and this uncertainty lends credence to Lively’s struggle.

And what a struggle! Lively takes a beating in this movie, which features the most grueling bit of self-surgery since 127 Hours. Her body is raked across pointed coral, she’s bashed on rocks, and bitten, more than once, by carnivorous ocean life. Those dismayed by the PG-13 rating needn’t worry, it’s a grueling little movie in the best possible way.

The shark attacks are largely CGI, but Serra never allows this this enter SyFy territory. He focuses on nightmarish imagery you’ll remember long after you’ve left the theater: like a shark gliding through a rising wave, or the money shot that’s unfortunately been used in nearly every piece of marketing. Only Lively’s encounter with a school of jellyfish seems a little unconvincing, although there’s hardly enough time to linger on it. And there’s plenty of other moments that should rekindle our collective suspicion of the ocean, which is precisely the impact this kind of movie should have.

The Shallows is survival horror, but that doesn’t stop Serra from having fun with the proceedings. This subgenre tends to be incredibly morose, with the ultimate irony being that people don’t often survive it. Serra seems determined to run in those waters while circumventing our expectations. So when The Shallows introduces a delightful seagull sidekick that spends a good chunk of the movie by Lively’s side, it’s a welcome change of pace. I can’t think of another movie with a seagull sidekick, but even if The Shallows isn’t the first to have one, Steven Seagull is surely the best of them. Lively’s scenes with the bird offer quick bursts of levity in a movie that would otherwise have none.

Adding to the sense of fun is an exciting final third, which gives Lively the opportunity to fight back against the monster in a way that establishes her as a badass horror heroine. If the movie plays fast and loose with logistics during its climactic battle, these liberties are earned because Serra has kept us gasping throughout, and every great craftsman understands that a strong catharsis is the best payoff. I’m not spoiling Lively’s ultimate fate by talking about this, I’m only saying that her final battle for survival is as good as they come.

The Shallows is a tense thriller, no doubt. It doesn’t break new ground. It doesn’t have to. It’s fun and engaging and it draws you in from the beginning. This is Serra’s third horror film (behind House of Wax and Orphan). While I mean no disrespect to his trio of Liam Neeson thrillers, I much prefer his genre work and he’s 3/3 from where I sit. There are plenty of talented filmmakers out there delivering shocks to modern audiences, and Serra is among the best of them. After surviving a swim through The Shallows, I sincerely hope he’ll keep doing it.