Entertainment

It’s open season on the 47 percent in so-so satirical thriller ‘The Purge’

As dystopian thrillers go, “The Purge’’ has a better premise than most we’ve seen recently: In 2022, the “New Founding Fathers’’ (read: Tea Party) have ushered in a “rebirth’’ of American prosperity by instituting an annual “purge’’ when all laws, including the crime of murder, are suspended for 12 hours of mayhem.

There are still enough bleeding-heart liberals around to complain on TV that this amounts to an open season on what a recent presidential candidate unfortunately termed the 47 percent.

But after a wickedly promising start, this pointed political satire quickly deteriorates into a fairly routine, if sporadically quite effective, home-invasion thriller.

One wag at the other night’s screening dubbed this “Before 7 a.m.’’ because of the clever casting-against-type of “Before Midnight’’ star Ethan Hawke as a wealthy salesman of home-security devices.

A scene from “The Purge” (©Universal/Everett Collection)

He gathers his family safely (he thinks) behind the steel shutters of their McMansion in a gated community when the annual slaughter (police and medical personnel have the night off) kicks off at 7 p.m.

No sooner has our hero settled in to watch the nationwide carnage on TV than he accidentally kills his moody daughter’s boyfriend, who Dad has mistaken for an intruder.

Hawke has less luck tracking down a homeless black man (Edwin Hodge) his geeky son has allowed to take refuge inside the home — so he can turn him over to a 21st-century lynch mob.

That members of the bloodthirsty mob wear masks seems to have less to do with the rules of the movie (after all, their activities are temporarily legal) than with writer-director James DeMonaco’s desire to pay homage to “A Clockwork Orange’’ — as well as well as a raft of other, more effective movies ranging from “Straw Dogs’’ to “Funny Games.’’

When the mob’s preppy leader (an over-the-top Rhys Wakefield) demands that Hawke turn over the “homeless pig,’’ the cowardly Hawke readily agrees to do so after sheepishly admitting that their home is, indeed, not invulnerable to the mob’s threatened onslaught.

What follows is a dull search for the interloper inside the darkened home (the mob has cut the power). “The Panic Room’’ it’s not.

With most of the scares coming from poorly executed shock cuts, this makes the film seem far longer than its abbreviated running time.

“The Purge’’ does deliver the gory genre goods in the highly predictable home stretch, and even returns to satire at the end. Let’s just say that Lena Heady, underutilized as Hawke’s wife, ended up with the biggest of several rounds of applause in the last five minutes.

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