Gangster Squad (R) ★½

Gangster Squad, the new movie from genre-blending filmmaker Ruben Fleischer (Zombieland), has a tone problem. The scatterbrained approach to the vigilante tale is summed up in one particular sequence: the ''Squad,'' cops given permission to take down the goons of Los Angeles gangster Mickey Cohen (Sean Penn) by any means possible, bust a dope smuggling operation at an airport in Burbank. Instead of tailing the criminals making off with the drugs, they engage them in a car chase, full of gunfire, explosions, and hyper-stylized, CG-assisted camera work. When they finally do capture Cohen's men, the squad leader Sgt. John O'Mara (Josh Brolin) interrogates them, then shoots the cowering thugs in the back of the legs, before rolling them down a hill. Within seconds, the movie jumps from outlandish comic book roller coaster ride to gritty crime fiction, exploring the moral complexity of defeating crime lords. The two mix onscreen like water and oil.

Fleischer packs it all into Gangster Squad, and rarely does any of the material shine. Brolin works as the hard-nosed policeman dedicated to justice, physically perfect with beady eyes and a square chin. But that's all his character has to offer, with his squadron offering even less. Ryan Gosling appears as the whippersnapper cop on the verge of corruption, expressing his doubts with the whiniest '40s accent ever to grace the screen. Anthony Mackie, Michael Pena, Giovanni Ribisi, and Robert Patrick fill out the group — after sleek, Ocean's 11-style introductions — bringing identifiable traits that open the door for one or two oh-right-that's-why-you're-here moments throughout the film. They feel barely existent in Gangster Squad's zippy script, convinced to work outside the law all too easily, and following O'Mara into suicidal missions that likely have sounder alternatives. For O'Mara, whatever takedown creates the biggest mess — be it the aforementioned chase or setting a Cohen-owned club aflame — is top priority.

The saving grace is Penn, playing Cohen like a long lost castmember of Warren Beaty's Dick Tracy. Every moment he's on screen, Penn is scarfing down scenery and spitting it in our faces, going over the top and sticking to it. He loves money, he loves women, he loves fudge sundaes. Penn makes a choice, one the movie desperately needs. Surprisingly, Emma Stone can't keep up as his arm candy Grace Faraday, who falls head over heels for Gosling because it's an old fashioned noir throwback and, well, you certainly can't have one without hammy dialogue and paper thin romance.

The nods to Hollywood's golden era upgraded with flashy costumes and special effects would work if Gangster Squad didn't insist on bringing reality into the picture. Too often, the movie resorts to moments of shocking violence, much of it intensified by the slow motion shots of a tommy gun. The violence is raw, while the film surrounding it is cartoonish. The choice raises questions Gangster Squad never answers: is O'Mara in the right when he takes the law into his own hands? Ribisi's techie character — a WWII vet like O'Mara and someone deeply changed by his war experiences — asks these questions, challenging his boss' choices. Briefly. O'Mara, and the film, brush off the debate any time it comes up, making room for more slick scenes of action.

Muddled in some of the most heinous digital photography in recent memory (no exaggeration: half the movie is motion blur), Gangster Squad is an experiment in modernization gone wrong. As Brolin and Penn trudge their way with entertaining choices, Fleischer's film goes rogue around them. In this case, entertaining outside the law doesn't work.

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Hollywood.com rated this film 1 1/2 stars.