Another ‘roid-raging dirty cop drama from David Ayer, who scripted Training Day (2001) and Dark Blue (2002) before making his directorial debut with the overlooked Harsh Times (2005). This time the embittered blue knight is a widowed LAPD detective (a beefy Keanu Reeves) who’s being fingered by a department whistle-blower and has the bad luck to be in a convenience store with him when the guy is pumped full of lead by drug dealers. The script is by Jamie Moss, James Ellroy (L.A. Confidential), and Kurt Wimmer (Ultraviolet), but it preserves the peculiar machismo of Ayer’s earlier projects: the alpha male dominates not only because he’s the most powerful, but because he’s the most jaded. With Forest Whitaker, Hugh Laurie, and Chris Evans. R, 109 min.