Men in fedoras lurk in dark alleys with the aim of cleaning up Los Angeles in 1949, when notorious gangster Mickey Cohen has a stranglehold on the town - especially the LAPD. It's the stuff of old-fashioned film noir made shiny and new; a gloriously guilty pleasure given extra weight by a line-up that includes Josh Brolin, Ryan Gosling and Sean Penn.
Brolin looks to be the last good cop in town as Sgt John O'Mara, but that may be because he's more brawn than brains. His fellow sergeant Jerry Wooters (a typically smooth Gosling) reckons that if you live in a cesspool of crime and corruption you should "buy a bathing suit" and just get on with it. That is until the mob guns down his favourite shoeshine boy in a frenzied ambush.
Wooters is already sleeping with Cohen's main moll Grace (a dewy-eyed Emma Stone, not quite playing against type), but he keeps that on the down-low, for her sake, and seeks vengeance by joining O'Mara's 'Gangster Squad', a secret taskforce appointed by Nick Nolte's grizzled chief of police, who's decided to make a stand against Cohen - as long as he's not up front.
It appears to be a fool's mission, with O'Mara leading Wooters, wiretap expert Officer Keeler (Giovanni Ribisi), sharpshooting Officer Kennard (Robert Patrick) and Officer Ramirez (Michael Peña) into a series of violent raids on Cohen's bars, clubs and casinos, the first of which plays like a slapstick farce. But the plan also guarantees a steady stream of adrenaline-pumping action.
This is the perfect, big-budget playground for director Ruben Fleischer, who brought us the wryly amusing 30 Minutes or Less and Zombieland. He takes an ostentatious approach to scenes of violence, employing slow-motion and cranking up the volume on a chorus of machine guns. But the dialogue also has that rat-a-tat feel and his editing equally betrays his dark sense of humour - like a cut from a brutal killing to hamburger grilling at a barbecue.
Fleischer isn't subtle. This is a blast in every sense, but fans of the similarly themed LA Confidential may be disappointed to find this lacks the scathing insight into departmental politics. It is, after all, based on truth (a book by LA Times journalist Paul Lieberman, adapted by ex-cop Will Beall) and the less obvious pressures that O'Mara and his crew must have endured, daily, go unaddressed.
Without a fine cast of actors this would just be a high-gloss caper. Brolin holds steady as the man who seems to be carrying the world on his shoulders, though he's regularly upstaged by Gosling with a cool, offhanded approach, gradually fraying at the edges. Ribisi is quirky as always, yet quietly noble, and Penn is just downright scary with a heart-piercing, droopy-eyed stare.
There are shades of The Untouchables in a final, explosive showdown at the Park Plaza Hotel, but again, the comparison doesn't extend to any deeper conflict that members of the Gangster Squad will have had to have faced. Accept the film on its own terms, as a period action thriller, and you'll walk away satisfied - assuming your every last nerve hasn't been jangled to jelly.