After being canned for three years (allegedly due to pressure from the Los Angeles police department) Brad Furman’s “City of Lies” was rolled out last month.

Although it would have benefited from a longer running time and deeper examination into the facts (this story would shine as a three-hour street crime epic), Brad Furman’s procedural gets to the meat of the inquiry into the murders of the Notorious B.I.G. and Tupac Shakur and the breaking open of the Los Angeles Rampart scandal, one that involved dirty cops working for street gangs and mobsters like Suge Knight.

Based on the best-selling book “LAbyrinth: A Detective Investigates the Murders of Tupac Shakur and Notorious B.I.G., the Implication of Death Row Records’ Suge Knight, and the Origins of the Los Angeles Police Scandal” by journalist Randall Sullivan, the film stars Johnny Depp (who is finally delivering a performance that is of this Earth) as Russell Poole, the L.A.P.D. detective who discovered that members of the force were conspiring with Knight in a murderous plot against Tupac and Biggie.

The case that Poole unravels is a pandora’s box of corruption. The suspects and the trails they leave are serpentine but screenwriter Christian Contreras lays it all out while avoiding a surfeit of facts.

Forest Whitaker does excellent work as “Jack Jackson,” a reporter based on the real-life Randall Sullivan. Whitaker has long been one of our most reliable character actors but, after winning his well-deserved Oscar for playing Idi Amin, the actor has fallen prey to histrionics with most of the roles he chooses. Here Whitaker is more internal, projecting emotions without yelling and mugging.

Actors Dayton Callie and Shea Wigham have essential supporting roles and use their limited screen time effectively. Callie and Wigham have earned their reputation in film and television, both thespians making the intense moments count.

Toby Huss’s detective Fred Miller has to walk a thin line on the side of straight and crooked but is neither villain nor hero and shows a moral backbone when the occasion calls. Michael Paré (“Streets of Fire”) plays detective Varney.

In 1997, an apparent case of road rage in which a white man shoots and kills a black man, turns into a possible sanctioned execution between two crooked cops. As investigators arrive in the scene, the white man reveals he is a police officer named Frank Lyga, who felt his life was in danger. The man he just shot is also found to be a cop named Kevin Gaines, who had gone too far undercover.

As Poole is the lead detective on the scene, this is his entry to the first hints of a conspiracy. He discovers that Gaines was in the employ of Suge Knight and may be directly involved in the killings of the two rap artists.

As Poole states in a well-written voiceover, “That day on that street corner, the first door to the labyrinth opened.”

Screenwriter Christian Contreras lays out the facts in an interesting manner, examining the myriad components that led to the massive police scandal. Furman leaves breathing room for the story to evolve but his film does hit a few potholes.

At times, Furman and his composer Chris Hajian over-score the film, showing an apparent lack of faith in the quieter moments. A few great dialogue-heavy scenes between Depp and Whitaker are almost done in by unnecessarily intrusive sound.

In turn, many of the song queues are uneven. I realize that Tupac and Biggie’s music must be heard but I am not sure the director had a firm enough grasp on how to properly use them to their dramatic potential.

While it remains a fascinating case, Furman’s film adds nothing to the conversation regarding these murders. This cannot be helped, as the film was shot in 2016 and its released held up until now.

Furman’s style is also clunky at times. He evidently wanted his film to be a sharp examination of a real-life incident while keeping “City” crime thriller-friendly. The two styles never quite come together but first-rate performances and a fascinating tale kept me watching.

With his focused performance as Poole, Johnny Depp reminded me of what forceful presence he can project. The detective has become an outsider for taking a stand against corruption. His “brother” officers are that no more. Poole has lost his job, his reputation, and his family for doing what he must. But the detective has not given up his drive and continues to piece together the puzzle of corruption. He is defeated as a cop and a husband and father and all he has left is the truth he has uncovered. Depp is so good as Poole.

Ultimately “City of Lies” is a win. And though it lacks dramatic oomph Furman and his cast have made “City of Lies” a worthy and compelling film.