How dangerous are the lions in "Beast?" So dangerous that when characters hear a nearby noise and discover it's "only" a man-eating crocodile, they are relieved.

The thrill of "Beast" is watching humans — specifically Idris Elba, with his ideal shoulders-to-waist ratio — get very up close and personal with lions. And even though we know the lions are special effects and that Elba was never in danger of being taken out of the "next James Bond" sweepstakes, the escalating battle scenes are incredibly effective.

Director Baltasar Kormákur doesn't make classic movies, but films such as "Contraband" and "Jar City" have proven he knows his way around a briskly efficient action sequence. He delivers a bunch of them in "Beast," which finds a doctor (Elba) and his daughters (Iyana Halley and Leah Jeffries) on vacation in South African bush country.

Soon, they're stranded in the middle of nowhere, at the mercy of a vicious lion and, to quote the last "Jaws" movie, "This time it's personal." Think of this one as "Paws."

It takes some time for the movie to divulge why this lion is overlooking his usual prey in favor of human meat, and animal behavior experts may not be impressed by the explanation. But it serves its purpose in "Beast," which just wants us to be gripped for 90 minutes as three resourceful people try to MacGyver themselves out of tight spots, with no rescuers on the way.

Screenwriter Ryan Engle tosses in some family melodrama that "Beast" doesn't need and that Kormákur, wisely, bats aside like a lion toying with a gazelle. What Kormákur cares about is lion attacks. They include one with the three leads trapped in a car, another under a tree and another in grass so tall that we're only aware of the invisible predator because of the grass' sudden movement — not unlike the telltale tail fin in "Jaws."

Kormákur, his special effects crew and the actors choreograph and execute these scenes for maximum tension, with each strike by the lion a little more vicious, a little more effective (good thing Elba's character is a doctor, since he has a lot of wounds to dress) and — despite the wide open spaces — a little more claustrophobic.

The "Beast" trailer makes it look almost campy. If that's the movie you're hoping for, you'll be disappointed. The man-on-lion fights strain credulity, sure, but "Beast" is played with a straight face. And because the action is so compelling and the film itself is so modest, it succeeds by a whisker.

'Beast'

*** out of 4 stars

Rated R for bloody violence.

Where: Area theaters.