Sure, he’s a murdering shitbag—but don’t call him a rat!

Joe Berlinger made his name as codirector of the Paradise Lost trilogy, the epic trio of documentaries about an Arkansas murder investigation that went places the filmmakers couldn't have imagined and actually changed the course of history. With his new Whitey: United States of America v. James J. Bulger, Berlinger again dives into a sordid crime saga, one that's possibly even twistier.

The twistiness of the James "Whitey" Bulger story begins at the roots, with the fact that there is no one Whitey Bulger story—"the Whitey Bulger story" is, as much as anything, a fight to establish said story, with two narratives battling it out for prominence. The first story, put forth by prosecutors during Bulger's 2013 murder trial, paints Bulger as a ruthless killer and blackmailer who lorded over the streets of South Boston as a non-mafia crime boss during the '70s and '80s, while simultaneously serving as an informant for the FBI.

The second story, put forth by the man himself, paints Bulger as a ruthless killer and blackmailer who lorded over the streets of South Boston as a non-mafia crime boss during the '70s and '80s—but who never, ever cooperated with the FBI or any other law enforcement agency. His extensively documented interactions with the FBI were, Bulger attests, based not on him providing information to the Feds, but on corrupt FBI agents selling info—about wiretaps and impending indictments—to Bulger.

The documentary follows the course of Bulger's 2013 trial, into which no cameras were allowed, leaving director Berlinger to run audio recordings of trial proceedings while filling the screen with panoramic shots of Boston and highlighted text of key testimony. The device works well in regard to the city, showcasing Boston as a key character in the story, but things get a little sweaty when Berlinger reconstructs courtroom scenes through one-sided reenactments. The sworn testimony of career criminals is dicey enough, and reenactments render it close to worthless.

Still, after Whitey's key characters and contending forces are established, the film achieves a brutal velocity, fueled by riotously clashing stories, heartbreaking twists, and an ever-intensifying spotlight on the alleged wrongdoings of the FBI, which is accused of letting a hunger to bust the Italian mafia drive the agency into an allegedly criminal alliance with a murderous psychopath.

It's the type of documentary that sends you out with more questions than you came in with. With so many angles of contention, the conspiracy theories are limitless, especially when drawing upon the imaginative resources of ass-covering criminals, closure-seeking survivors, and a Federal Bureau of Investigation eager to preserve decades of convictions. "Memory is a political act," one Boston journalist proclaims, vowing to instill the key fact in the public imagination: James "Whitey" Bulger is a ruthless killer and blackmailer who destroyed countless lives. Ultimately, it's these lives that give the film its emotional heft: the brother of a woman killed for knowing too much, the wives of victims of mistaken hits, the small, haunted lives you never see in Scorsese films. recommended