ZERO DARK THIRTY: 4 STARS

Alfred Hitchcock famously described how to create tension in a movie. "There's two people having breakfast and there's a bomb under the table,” he said. “If it explodes, that's a surprise. But if it doesn't..." I’ll finish the sentence he so anticipatorily left undone: “…that’s suspense.”

“Zero Dark Thirty” (refers to the military time for thirty minutes after midnight) operates on this premise, creating suspense even though many of the bombs do go off and we know how the story ends. The whole movie is the bomb under the table, leading up to an explosive, although protracted, climax.

The film begins on 9-11 with audio of calls coming from the Twin Towers. Stage set, the movie leaps forward two years to the brutal waterboarding and torture of an Osama bin Laden relative by Dan (Jason Clarke), a CIA expert in extracting information. “In the end everybody breaks,” he tells his subject. “It’s biology.” Overseeing the waterboarding and humiliation techniques is Maya (Jessica Chastain), a newly recruited officer charged with helping to track down terrorist leader bin Laden and dismantle al-Qaeda.

This is Maya’s story. It’s a carefully plotted espionage tale that flows from the clues that lead to the death of bin Laden at the hands of the Navy S.E.A.L. Team 6 in May, 2011.

“Zero Dark Thirty” is not a who-dunnit, or why-dunnit, but a how-dunnit.

It’s a detailed look at the step-by-step process that resulted in locating and exterminating bin Laden. The story begins before President Obama’s famous, “We don’t torture,” speech about regaining “America’s moral stature in the world,” so it presents the uncomfortable, controversial truth that pitiless persuasion like sleep deprivation, boxing and waterboarding-so simple, yet so brutally, terrifyingly effective-was used to gain information.

That queasy feeling from the film’s opening torture scene-that unethical techniques were used to gain information-evaporates during the daring Abbottabad raid sequence. While there’s a political discussion to be had regarding the ethics of waterboarding, that’s for another column. Dramatically it helps to provide a starting place for what is essentially a procedural.

Director Kathryn Bigelow and journalist-turned-screenwriter Mark Boal have focused on the details, shying away from delving into the personal lives of the characters.

Chastain’s Maya is a cipher, we know little about her except she was recruited out of school by the CIA and has spent a decade chasing one goal. Her selfless, obsessive dedication has perhaps cost some of her humanity, but Chastain manages to create an interesting character even when she has to mouth hyperbole about her noble quest. “A lot of my friends have died,” she says. “I believe I was spared so I could finish the job.” That’s a line straight out of any generic action movie.

But this isn’t a generic action movie. It’s a nuanced, suspenseful and terrifically exciting look at recent history.

Frequent overwriting the inevitable “then I’m gonna kill bin Laden” moment and CIA honchos who say things like “Do your jobs and bring me people to kill,”-seems too easy for a movie this clever, but Bigelow’s virtuosic handling of the climatic raid scene overpowers the film’s weaker moments.

GANGSTER SQUAD: 2 ½ STARS

It’s Los Angeles, 1949. Ruthless gangster Mickey Cohen (Sean Penn in over-the-top-mode) has taken over the city. There’s brothels, booze and bad news all over. “I’m building a new city out of the ruins of Los Angeles,” says Cohen.

Corruption is the name of the game for everyone except Sgt. John O'Mara (Josh Brolin), a honest cop in a crooked town. When LAPD Chief William Henry Parker (Nick Nolte) asks him to create a special undercover team to bring Cohen and his thugs to justice, O’Mara assembles the Gangster Squad, a group of cops who don’t mind getting their hands dirty.

“The Gangster Squad” will likely suffer from the inevitable comparisons to “The Untouchables” and “LA Confidential.” It grabs the atmosphere of post war LA from the latter and the storyline, almost beat for beat, from the former. There’s even a shoot out on a stairway, but this is a far more blunt object than either of its forbearers. In the first 20 minutes people are drawn and quartered, incinerated-apparently Cohen prefers medieval techniques- and there’s a vicious fistfight. Then it gets violent.

The film is possibly best known, not for its cast, which also includes Ryan Gostling, Emma Stone, Michael Pena and Giovanni Ribisi, but as the movie pulled from release following the Aurora, Colorado Century 13 massacre. Originally featuring a scene of gangsters randomly firing into a movie theatre, it was deemed inappropriate for release at the time. I’m not sure what they have replaced that scene with, but trust me, its removal hasn’t made the film any less violent in tone.

It’s a gorgeous looking film, with a pretty picture of LA’s glamorous nightlife and features dialogue by Will Beall who has clearly spent some time watching Raymond Chandler movies like “The Big Sleep.” Lines like “The whole city is underwater and you’re grabbing a bucket when you should be grabbing a bathing suit,” have more finesse than the story as a whole.

“The Gangster Squad” is a period piece that spends a bit too much time exploring the down-and-dirty side of the story, but it is a stylish look at a violent time.