Black Mass is the story of James "Whitey" Bulger's rise to prominence as the preeminent gangster in Boston in the 1980s. Essentially, he agrees to cooperate with an FBI agent, his childhood friend, to take down the Italian mob in exchange for immunity from prosecution. Bulger constantly pushes the boundaries until his FBI accomplice has to misdirect suspicions and get the heat off Bulger's crew again and again. It doesn't hurt that Bulger's brother Billy is a state senator. Having any vocal opponents or threats disappear in a bullet-soaked haze isn't too bad, either.

Black Mass is a slow and surprisingly quiet crime drama. The pace doesn't even really pick up until the last 40 minutes. Director Scott Cooper is content to linger on quiet, everyday conversations in the lives of Bulger and his accomplices. It just so happens that these conversations are almost always about horribly illegal activities, like murder, murder for hire, racketeering, and silencing rats.

The acting in the film is excellent across the board. Johnny Depp gives his best human performance (as opposed to kooky quasi-fantasy performance like Edward Scissorhands or Captain Jack Sparrow) ever as Whitey Bulger. Depp's Bulger is terrifying. He's totally unpredictable because the face doesn't crack. You can only read his intentions through tiny shifts in vocal cadence. There's only one moment in the entire film where he looses his cool and it has nothing to do with criminal activity. He's a living monster with piercing blue eyes and more brains than anyone else in the room.

The band of agents, politicians, and gangsters surrounding him provide more of the emotional levels of the film. Joel Edgerton slowly transforms into a monster as FBI agent and childhood friend John Connolly. Benedict Cumberbatch is standoffish and charming in the best possible combination as the ever-popular Senator Billy Bulger. Peter Sarsgaard steals the show for a good chunk of the movie as hot-headed hitman Brian Halloran and Juno Temple takes center stage in one of the most shocking scenes as young prostitute Deborah Hussey.

The makeup and hair work in Black Mass is incredible. It's not flashy, but it is expansive. The film goes through the better part of three decades, with the hairstyles updating on the largely male cast to reflect the times. There's also very natural and believable makeup used to age the characters up. That's not even getting into the perfect execution of injuries and blood in action scenes and the accurate lingering injuries from black eyes, cuts, and broken noses.

A major conceit of the film is gangsters testifying against Whitey Bulger to segue between time periods. These actors look like they've lived rough and violent lives judging by the present, yet the past shows how slowly they transformed into these broken specimens.

Black Mass is a quiet, well-executed crime drama focusing on an intriguing novelty in the history of American organized crime. Irish gangsters controlling major cities and wielding international influence went out of favor in the early 20th century until Whitey Bulger seized power with the help of the FBI. It's an interesting case study in unintended consequences in the pursuit of justice.

Black Mass is currently playing in theaters.