Even when Michael Mann was making The Insider, he knew it would become a target, so the filmmaker did everything he could to protect it from those who didn’t want its story to be told. Except—there was a possible spy involved in the production. At least one. Or so he believes now, looking back a quarter century later.

The glossy Hollywood thriller was based on a true-life story that exposed corporate lies, media cowardice, and a conspiracy to deceive the public that impacted the health and well-being of millions around the world. With trust in the media now in free fall, billionaires appear to manipulate which messages become widely shared and suppress views they dislike, and “believe the science” means different things to different people based on political ideology. The Insider is as powerful now as it was prophetic then. That’s why it had enemies.

Mann was always braced for attacks. “I was very proactively protective,” the filmmaker tells Vanity Fair for the 25th anniversary of the 1999 movie, which garnered seven nominations, including best picture, director, and adapted screenplay. “Our editing room was designed with security protocols by a guy who had set up the security of the US embassy in Moscow. You couldn’t just walk into our editing room. It was not in some studio bungalow. It was off the lot.” But that might not have been good enough. Mann later came to suspect that The Insider had its own insider.

The film dramatized the real-life story of tobacco industry whistleblower Jeffrey Wigand, who was played by an aged-up and dowdy Russell Crowe. Wigand was a vice president of research at Brown & Williamson who suffered a crisis of conscience in the mid-1990s and publicly revealed internal research that showed his employer not only knew that smoking caused severe health problems but also engineered the product to be more addictive. Today, believing anything otherwise seems naive, but for decades the companies that made up Big Tobacco tried to maintain a sense of doubt in the minds of their customers.

Adding to the intrigue, Wigand’s documentation was investigated and vetted in 1995 by the CBS news magazine 60 Minutes—which subsequently caved to pressure from CBS counsel and leadership to soften the report. As word of this leaked out—by way of the segment’s outraged producer, Lowell Bergman (played by Al Pacino)—the smoking gun of smoking’s consequences became an even bigger controversy.

Mann didn’t want his movie to suffer the same meddling. The Insider could become legally vulnerable if Brown & Williamson saw an opportunity to pounce on producer Touchstone Pictures, a division of the Walt Disney Company. “Brown & Williamson wrote a threatening letter to Disney,” Mann recalls. That may sound like a case of Goliath versus Goliath, but the filmmaker notes that at the time, “Brown & Williamson’s annual revenues exceeded the book value of Disney.”

To shield the movie, Mann fortified his production against prying eyes. Or at least, he tried. “All of our internal connectedness was highly secured,” the filmmaker says. That “connectedness” meant all the memos that Mann regularly fired off to the various department heads as the movie was coming together. This is when the director, previously best known for Heat and Miami Vice, believes a mole might have become involved. Mann had no idea until it was all over.

“I do a lot of dictation. I dictate notes on dailies, I dictate notes on costs, I dictate everything. It all gets transcribed,” Mann says. “And one of the transcribers, we found out later on, was actually a former employee of Brown & Williamson’s law firm in Kansas City.”

Is he one hundred percent certain that this individual was used for purposes of espionage? No, but Mann thinks the coincidence is too unusual to overlook. At the very least, Mann wonders if the cigarette maker’s representatives used this person as a window into the making of the movie throughout its creation. “I don’t know that [the transcriber] ever gave any information, and certainly [Brown & Williamson’s] law firm never did anything, I think, because there never was a suit,” Mann says. “But we found out later on that this guy actually had a work history.” And Mann feels confident that history traced back to the tobacco business.

The cigarette giant, which merged with R.J. Reynolds in 2004, might have had nothing left to hide by then. The suppression of the 60 Minutes report had already been exposed to tremendous outrage, including in a May 1996 Vanity Fair article by Marie Brenner, “The Man Who Knew Too Much,” which served as source material for The Insider. Brown & Williamson was also among the handful of major tobacco distributors that agreed in 1997 to a landmark $368.5 billion settlement with 46 states, many of which had filed Medicaid lawsuits over ailments caused by their products.

Despite reeling from these embarrassments and losses, Brown & Williamson might have seen an opportunity to strike back had the Hollywood version of the Wigand story taken enough liberties to justify an injunction that blocked release or opened the door for a defamation lawsuit against Disney (or the filmmaker himself).

Mann had a second line of defense beyond his office security protocols: The movie told the truth.

Mann recalls that Disney’s then studio chief, Joe Roth, and the company’s general counsel, Joe Shapiro (who died in September 1999, one month before the film’s release), were willing to stand by The Insider, but only if Mann followed the same journalistic principles that his movie purported to champion. “Every line of dialogue, every description had to be corroborated,” Mann says. “So we produced another screenplay—it was about 300 pages long—which had the sources of absolutely everything that we put into it.”

From the Archive: The Man Who Knew Too Much

As a result, Mann and co-screenwriter Eric Roth (an Oscar winner for 1994’s Forrest Gump) had to present certain elements of the story as mysteries, rather than make bold claims. “There was a bullet in the [Wigand family] mailbox, and we heard from good sources that this firm of private investigators planted that bullet there,” Mann says. “We couldn’t corroborate it one or two more times, so we turned it into an ambiguity: ‘Was Wigand responsible for the bullet? How did the bullet get there?’”

That left only one other worrisome opponent: Mike Wallace, the imperious TV newsman who was the anchor of the compromised 60 Minutes report.

Wallace was played in The Insider by Christopher Plummer, and although the depiction was mostly flattering, the real broadcaster saw this story of the cigarette whistleblower incident as a stain on his otherwise sterling reputation. “The basis of the film was that I had lost my moral compass and had gone along with the company and caved in for fear of a lawsuit or something like that,” Wallace said in a 2002 interview with the nonprofit Academy of Achievement. “That was utter bullshit. It was done for the drama involved. Then finally, at the end, I found my moral compass again, except it was not true.”

Wallace, who died in 2012, grumbled about The Insider for years. Before that, he worked to gain insight into the project while it was in the midst of production. Wallace came at the filmmaker directly—and Mann was happy to go toe to toe with him. In some ways, the director was charmed by the journalist’s bulldog demeanor. “First of all, I really liked Mike Wallace,” Mann says today. “You couldn’t help but like him.”

The movie depicts Wallace siding with longtime 60 Minutes producer Don Hewitt, who died in 2009, and bowing to concerns from CBS leadership over the Wigand segment. There was no uncertainty about the truth of the report, but executives worried it might nonetheless spark costly litigation that could disrupt a planned sale of the network. “Don had indeed gone along with the company, and I had for a period of maybe about 12 hours,” Wallace said in the 2002 interview. “And then I said, ‘Uh-uh, I’m not going to do this.’”

The undeniable fact was that the legendary newsman did falter, if only briefly. The dispute with Mann was over how briefly. “I’m sorry he was so sensitized to his image. I really wish he hadn’t been,” Mann says today. “No, this falter was more than 12 hours.”

The filmmaker had unique insight into Wallace’s backroom conversations with the producer and CBS because he had his own insider in the 60 Minutes conflict. Mann knew Bergman personally at the time. Both were graduates of the University of Wisconsin, and a mutual friend in the Drug Enforcement Administration had introduced them years before the production of The Insider. When Bergman was in the throes of the tobacco whistleblower battle with CBS brass, he and Mann were also collaborating on another film project in 1995, about an infamous international arms dealer. “I was one of about 10 people who Lowell would talk to on a regular basis about tobacco and Wigand,” says Mann, who remains close with Bergman today. “I said, ‘Forget the arms merchant. What you’re living through right now is so profoundly moving and powerful of a story. Let’s make that movie.’ And that’s how it began.”

Wallace reached out to Bergman when he heard an inter-office dispute was the subject of a screenplay. “I suddenly realized that Mr. Bergman had been forwarding all of this information to Michael Mann, an old friend of his, who was producing and/or directing and/or writing the film. So he knew everything that was going on in our shop at the same time that it was happening,” Wallace said in the 2002 interview. “I asked Lowell to get me a copy of the manuscript. He said he couldn’t do it.”

Bergman warned Mann to prepare for pressure from the newsman. “Lowell Bergman said, ‘If you think guys in Hollywood have thin skins, wait till you meet my guys,’ meaning Wallace,” Mann says. “On-camera talent suffers from the vanity of people who are often in front of the camera. And it’s unfortunate.”

Wallace’s primary complaint, for years afterward, was that he wasn’t consulted. “It was especially frustrating because I had never been contacted to get my side of the story,” he said in that 2002 interview. “This is ostensibly history, but no one—not the writers, not the producer—called me and said, ‘Mike, okay, we want to do this. Tell us your version of the story.’ Nothing of that sort happened.”

Mann says that wasn’t exactly true: “I had many conversations with him.”

Wallace himself confirms this, contradicting his claim in the very same interview: “I finally called Michael Mann and got a copy of the manuscript within 24 hours,” Wallace said in 2002. “I pointed out some of the wrong things in there, just outright dead wrong. Michael Mann corrected those, but he quite candidly said, ‘Look we need the drama.’ He didn’t say it this way, but ‘We need the drama of the fellow who loses his compass and finally gets it back and everything resolves itself.’ Well, what can you do under those circumstances?”

Mann acknowledges that Wallace did shape the story, but only by providing more accuracy and detail. In one of their calls, the broadcaster made a sarcastic remark that Mann later included in the movie. “He said, ‘Thank God I had Lowell Bergman to shine a light down the path of moral rectitude, or I would not have known which way to go,’” Mann says. “And I said, ‘Mike, do I have your permission to put that in this screenplay as dialogue from you?’ He said yes. So that’s there in the scene when Wallace goes to Lowell’s hotel room after Lowell spills [the story] in The New York Times.”

Mann seemed to have placated Wallace, at least for a time. Wallace did not interfere in the release of The Insider through any legal means, and appeared to soften around the time of its release. “Everybody is saying I really don’t look so bad at all in it,” Wallace said in a November 1999 interview with The New York Times.

At the time, Wallace claimed he had not seen the film, but in years to come he was still bristling about The Insider—or at least parts of it. “Two thirds of the film is quite accurate,” he said in 2002. “It was dramatized excessively.”

Mann still believes Wallace overreacted. “He faltered, and that’s human,” the filmmaker says. “Every character in this film is real in that sense. We all have flaws; it’s warts and all. And then he recovers. And the show airs! The take on Mike Wallace in the film—it’s not negative.”

Mann believes there are fewer Lowell Bergmans today risking everything to tell the truth, and he points out that wealthy executives are more brazen than ever about exerting influence over what the public sees and hears. “Probably the most relevant issue which we’re dealing with recently is ownership of institutional news media—obviously in the case of Musk, Bezos, Murdoch,” Mann says.

Mann feels social media promotes falsehoods that honest journalism can’t counteract, saying these platforms create an “exponential shrinking” that squeezes people into echo chambers. “That shrinking makes us vulnerable to waves of inflammatory attitude,” he says. “When removed from a sense of objective reality, it’s more about how an issue makes us feel than what an issue is.”

He isn’t optimistic things will get better. “I’m not one who believes that technology ever goes backward,” he says. “So this is our reality and it’s going to evolve and change, as I think it has in this recent election, in a very malign way.”

Ultimately The Insider was not strictly about the perils of smoking, or even the internal machinations of the news media. At its core, the film is about the cost of doing the right thing. Both Wigand and Bergman endured destabilizing career hits and suffered personal consequences for speaking out. Mann says the lesson of the film is that people should do what they know is right, even when it hurts.

“Where I start from is you look in the mirror, as we all do within the complexity of our own individual lives, and we ask ourselves, ‘Who am I? Do I measure up to my expectations of who I think I ought to be? Am I fucking up today? This year? Last month?’” he says. “That comes into sharp focus when faced with really significant, life-altering dilemmas.”