It’s 2022. and in the u.s. crime is at an all-time low. Why? Once a year, for 12 hours, the government condones robbery, rape and murder. Apparently, an annual purge clears our heads. Mr. President, are you listening? It’s a nifty premise, if you don’t think about it much. God knows James Sandin (Ethan Hawke) can deal with it. He’s making a killing selling home-security systems. During that 12-hour period, he locks up his wife (Lena Headey) and two kids (Adelaide Kane and Max Burkholder). It’s good to be a one-percenter. Until something goes wrong, which of course it does. What if a family member hears a stranger (Edwin Hodge) screaming outside, and lets him in just before the gates lock shut? What if your neighbors, some wearing masks, have a blood lust to get him? For starters, that’s a lot of “what ifs.” Hawke is strong and subtle at delineating the war inside Sandin’s head. And director James DeMonaco shows a sure hand at building tension. Too bad the film devolves into a series of home-invasion clichés. The Purge was almost on to something.