Roger Ailes passed away on May 20, 2017, but more than a year later his fingerprints remain all over America’s political and media landscapes. The strategist-turned-mogul who built Fox News into a conservative powerhouse—and then an outright propagandistic tool of the Republican Party and its current leader, President Donald J. Trump—Ailes flew high before crashing low after Gretchen Carlson, Megyn Kelly and others came forward with sexual-harassment allegations that ended his career. His influence on the culture can’t be overstated—nor can it be excessively vilified.

Divide & Conquer: The Story of Roger Ailes, premiering at this year’s New York Film Festival on Oct. 3 (and in theaters and VOD on Dec. 7), is a reasonably exhaustive portrait of the man and his global impact—which is to say, it’s as infuriating as any film you’re likely to see this year. Though Carlson and Kelly’s absence neuters some of its comprehensiveness (and potency), Alexis Bloom’s documentary nonetheless affords an illuminating window into the rarefied world of this titan, who rose from modest small-screen origins to become arguably the most powerful man in American TV. In reshaping the way news is designed and delivered, he reconfigured the national discourse itself, elevating the ferociously polarized us-versus-them paradigm that is, today, the depressing norm.

A “kingmaker,” Ailes was capable of making or breaking would-be stars (and presidents) on a whim, his canniness only matched by his ruthlessness. It was that latter quality, when paired with his fondness for demanding sexual favors in return for professional ones, that proved to be his undoing—and, as Bloom subtly makes clear, gave birth to a liberal movement that’s the antithesis of everything for which he stood.

“There was a Citizen Kane quality to his life,” says a colleague early in Divide & Conquer, thanks to the man’s love-hate relationship with his demanding father, who Ailes claims (via narrated passages from one of his books) was prone to wielding a belt to discipline his son. Supplementing that idea is the Ailes-favorite anecdote about his dad asking him to jump into his arms, only to pull away at the last second, with the lesson being: “Don’t trust anyone.” That story, it appears, was an inauthentic bit of myth-making. Bloom, however, contends that that ethos guided him from his earliest days working as a production assistant on The Mike Douglas Show. When Richard Nixon appeared on the popular TV program, Ailes convinced the presidential candidate to let him be his “media advisor,” and before long, he was on his conservative-mastermind way.

“ [Fox News] gave him an environment where he could peddle outrageous sensationalism for blockbuster ratings, with no regard for honesty, accuracy and decency. ”

Ailes’ famous success turning Nixon into a TV camera-friendly face—this after the disastrous 1960 debate with JFK that, conventional wisdom posits, helped lose him the race—made him a superstar. He’d subsequently aid Ronald Reagan with his 1984 re-election, as well as George H.W. Bush with his 1988 presidential campaign. It was there that he began perfecting his underhanded methods, most notably with the racist Willie Horton ads that torpedoed the fortunes of Bush’s opponent, Michael Dukakis. Shortly thereafter, Ailes headed to TV with the America’s Talking network. When NBC partnered with Bill Gates to transform it into MSNBC, Ailes—a perpetually angry man who always felt besieged, and was thus constantly looking for adversaries—joined forces with Rupert Murdoch to launch Fox News, where he oversaw virtually every aspect.

One Bill Clinton sex scandal later, and Ailes was on top of the world, riding the runaway success of Fox News. Divide & Conquer shrewdly posits the network as the manifestation of Ailes’ personality. It provided an outlet for his long-standing disgust for liberal elites, who he believed looked down upon the good family-values residents of places like his hometown of Warren, Ohio. It gave him an environment where he could peddle outrageous sensationalism for blockbuster ratings, with no regard for honesty, accuracy and decency. And it allowed him to perfect such ugliness—the muckraking, the conspiracy-theorizing, the warmongering—with savvy media techniques, including the casting of attractive female anchors and hosts for added surface-over-substance sex appeal.

“Riling up the crazies” is how a former O’Reilly Factor producer refers to Ailes’ exploitative modus operandi, and Divide & Conquer details the depressing bottom-line shrewdness of those tactics. Ailes’ tyrannical nature was echoed by Fox News’ screaming, bullying, culture war-inciting conduct, to outstanding results. It was also seen in his efforts to become the big man in Cold Spring, New York, where his purchase of the local paper and attempts to influence elections exposed the why-don’t-they-love-me insecurities lacing his above-the-law attitude. In trying to understand Ailes, Bloom occasionally flirts with unwarranted empathy. Fortunately, those moments are drowned out by the incessantly distasteful elements of his story, including his early study of Triumph of the Will to hone his media style, his paranoid habit of carrying loaded firearms, and his willingness to destroy those who dared exhibit anything less than unflagging loyalty to him and his mission.

Unfaithfulness and predation are, of course, what ultimately did Ailes in, as Carlson’s lawsuit opened the floodgates to myriad tales about his quid pro quo custom of trading sex for workplace favors. Those accusations became so undeniable that they eventually severed his relationship with boss Rupert Murdoch and led to his ouster, which was soon followed by that of Fox News star Bill O’Reilly, whom Bloom also finds time to rake over the coals. While the film’s mix of archival footage and recent interviews—with various on-air personalities and childhood friends—is of a stock variety, Divide & Conquer gets at a deeper sense of Ailes as a predatory egomaniac who was at his best (by which I mean, worst) when he had enemies to combat, and could use his network to pick those fights—or, as was the case in 2016, to elect a commander-in-chief equally eager to split the country apart.

As Divide & Conquer astutely illustrates, Ailes drove a wedge between the American left and right, even as he fueled the rise of both. On the one hand, his Fox News lives on as a mouthpiece for red-state MAGA extremism; yet on the other, his ruin at the hands of the many women he horribly mistreated has helped beget #MeToo and #TimesUp, which seek to overthrow the very backwards-looking ideology at the core of his cable-news brainchild. An evil genius who fashioned our fractured contemporary reality, as well as ushered in the forces seeking to dismantle some of its worst elements, he was, for better and worse, what he always wanted to be: a genuine history-maker.