PARANORMAL ACTIVITY 3 What's this? A horror film featuring creepy children? Why, I never....

WHEN A HORROR FILM becomes a horror franchise, it usually loses the ingredients that made it potent in the first place. New directors and writers take an effective premise and expand it into hoary mythologies: Jason takes Manhattan, the Leprechaun goes to the moon, and no one goes home happy.

In that light, it's to the benefit of the Paranormal Activity franchise that it relies on a simple, established formula: Man has weird feeling about his family home, starts recording surveillance footage, things escalate through gotcha scares, people die, roll credits.

Ostensibly a prequel to the preceding films, Paranormal Activity 3 feels more like a rewrite of a couple of rough drafts. With all-new leads and all-new directors (Ariel Schulman and Henry Joost, of last year's creepy, probably-fake documentary Catfish), the scares are smoother and the acting is less dubious. This time out the story feels much clearer, too, even if most of its DNA is made up of old horror standbys (babysitters in peril, creepy kids with "imaginary friends") and notes cribbed from other movies, most notably 2010's well-received found-footage horror flick, The Last Exorcism.

Familiar though the proceedings are, Schulman and Joost bring a remarkable amount of flair to them, grounding the cheap shocks in a creeping atmosphere of genuine dread. When our main character/amateur documentarian puts one of his surveillance cameras on the body of a modified oscillating fan, it's clear what we're in for: pan left, pan right, pan lef—OH GOD A GHOST. But the sheer obviousness of the setups gives the directors room to play with audience expectations in ways more stylish than the earlier Paranormal Activity movies. If the original Paranormal Activity had novelty on its side, but not much else, that novelty's long gone by now—but it's been replaced by some legitimately scary substance.