His friends begged him not to do it.

“They said I’d get killed,” recalls Nick Broomfield, director of the controversial new documentary “Biggie and Tupac.” And going into the project, the 54-year-old English director wasn’t so sure he’d make it out alive, either.

“For a while, I was imagining the worst,” Broomfield admits.

But delving into the unsolved murders of rappers Tupac Shakur and Notorious B.I.G. (Biggie Smalls) proved too juicy an adventure to let mortality stand in his way. The deaths (Tupac was gunned down in Las Vegas Sept. 7, 1996; B.I.G. was killed in a Los Angeles drive-by March 9, 1997) have long been linked to the East Coast/West Coast rap war of the late 1990s. One-time friends Biggie and Tupac became mortal enemies after Tupac accused the portly rapper from Bed-Stuy of organizing an attempt on his life.

Broomfield’s documentary posits, however, that the murders were orchestrated by Marion (Suge) Knight, founder of Death Row Records. The film alleges Knight had been bilking Tupac of millions in royalties and that the rapper was intent on leaving the label and founding his own. The movie suggests Biggie’s murder was meant to cover Knight’s trail.

To support his theory, Broomfield relies on several people, including former LAPD Investigator Russell Poole, who resigned after higher-ups thwarted his efforts to connect rogue cops to the Biggie murder. Poole says, “There’s information in the documentary even the police don’t have.”

Not everyone is buying the film’s allegations. Pulitzer Prize-winning reporter Chuck Phillips’ L.A. Times expose, which ran in early September, implicates Biggie in Tupac’s death. His story maintains that Biggie’s gun was used in Tupac’s murder, and that the rapper promised members of the Crips gang $1 million for the hit.

A spokesman for Death Row refused to comment.