Cohen, played by Sean Penn in “Gangster Squad,” was the lead instigator, a former boxer who became an enforcer with the Chicago Outfit, the powerful organized crime organization that was led by Al Capone during Prohibition.
After being sent to the West Coast to work with Bugsy Siegel, Cohen became a kingpin of booking operations after Siegel was killed. His rise was swift, and the LAPD's desire to rectify its reputation after a series of scandals helped speed the formation of O'Mara's division.
“Gangster Squad” mixes real-life characters such as Cohen, O'Mara, Gosling's Sgt. Jerry Wootens and surveillance expert Conway Keeler (Giovanni Ribisi) with composite characters such as Stone's Grace Faraday, a would-be actress who becomes Cohen's girlfriend and, eventually, Wooten's love interest.
Brolin said his character evolved considerably during production and postproduction, with the final portrayal of O'Mara being a laconic man of few words.
Compared with Penn's Cohen, a brazen outlaw who gives voice to every evil impulse in his arsenal, Brolin said the plainclothes detectives in “Gangster Squad” are men of quiet, unstoppable resolve, which creates a strong contrast when Brolin and Penn, who have been friends since the 1980s, finally square off.
“I think the fight with Sean was the most difficult, because Sean didn't rehearse as much as I did,” Brolin said, laughing. “So his fists were flying wildly during the fight. It was a tough fight that we rehearsed for many, many weeks and I love the way it turned out, but I think both of us, being the current and ex-smokers that we are, found it challenging — on an oxygen level.”
While “Gangster Squad” offers a colorful exploration of a Los Angeles that has largely disappeared, Brolin said that the heroes in this period piece represent a timeless value.
“It's the idea that you manifest something honorable and have an impact,” he said.
Travel and accommodations provided by Warner Bros.