Filmmakers Kirby Dick and Amy Ziering knew their documentary series “Allen v. Farrow” would generate a lot of headlines, given that it’s a deep dive into one of the most-discussed Hollywood controversies of all time: the custody battle between actress Mia Farrow and director Woody Allen, and his daughter Dylan Farrow’s allegation that he sexually abused her as a child. But even they didn’t predict the “seismic” response that they received once the episodes started airing weekly on HBO.

They heard from lawmakers glad to see the film highlighting “parental alienation,” a dubious and sometimes dangerous defense in court that is typically when a father accuses a mother of turning a child against them — a strategy used by Allen’s legal team and then popularized in other custody cases. They saw messages from legislators working on issues related to how children are treated in court. They received emails from incest survivors and therapists, grateful that a taboo subject was being discussed on a national platform.

And they saw quite a few viewers who had formed staunch opinions about the Allen and Farrow case long ago, only to find they changed their minds after watching the series. “They said they thought there was either no way to determine what happened, or that Mia Farrow was not a good mother,” Dick said. “But actually, once they’ve seen this and they really have all the facts, they have really shifted the way that they look at that.” (Allen has always denied the molestation allegation, and his representative called the documentary “a hatchet job riddled with falsehoods.”)

“Allen v. Farrow,” which recently concluded, is one of a string of recent celebrity-focused documentaries, including “Surviving R. Kelly,” “Framing Britney Spears” and “Leaving Neverland,” that has had an outsize impact. Not only can these projects change public opinion about A-list stars in a variety of ways, but they have resulted in consequences that not even the creators expected.

Ziering theorized that this is because we now live in a culture so increasingly saturated with news and alerts and social media updates that documentaries can serve as a 90-minute break to intensely focus on just one topic. Dick added it seems as if there has been a “renaissance” in documentaries over the past decade.

“Documentaries are this refuge from all the clatter. And there’s something very powerful … about how you really get to take an emotional journey,” Ziering said. “It’s a combination of information and emotions that make you more open to a deeper kind of reflection.”

Brie Bryant, Lifetime’s senior vice president of unscripted development and programming, saw that idea emphasized after the network aired “Surviving R. Kelly.” The series, executive produced by Dream Hampton, featured women who came forward with new allegations of sexual, mental and physical abuse they said they suffered by the R&B star. Rumors of Kelly’s sexual misconduct, often involving minors, were an open secret in the music industry for years and in his hometown of Chicago; in 2008, he was charged (and then acquitted) on 14 counts of child pornography after he was accused of making a sex tape with an underage girl. Regardless of the media coverage about him, it seemed as if Kelly, who denied all charges, would not face real repercussions.

But when the first season of the docuseries aired in early 2019, things abruptly started to change. Record label Sony dropped him. A prosecutor in Illinois called for potential victims or witnesses to step forward. The next month, Kelly was charged with 10 counts of aggravated criminal sexual abuse in Cook County, Ill., in which three victims were between 13 and 16 years old. That summer, he was arrested on federal sex-crime charges. He pleaded not guilty on all counts and remains in jail awaiting trial.

“The purpose of ‘Surviving R. Kelly’ was solely to create a platform and space for our survivors to do what the world ended up seeing, which was openly speak their truth and share their experiences without judgment,” said Bryant, who also served as an executive producer. “What unfolded afterward — a formal pursuit and investigations of these allegations — was just completely unimaginable, and I think unexpected, for all of us as producers. But especially for our survivors, some of whom have been literally screaming into the wind about this for decades.”

Bryant noted the #MeToo and Time’s Up movements that supported victims of sexual misconduct probably helped lay the groundwork for the positive reception of the series, which earned huge ratings for Lifetime and resulted in a follow-up season in 2020. Even though people might have read about the allegations before, there was something different about looking directly into the eyes of the women who shared their painful stories.

The Rape, Abuse & Incest National Network also reported that the week after the six episodes aired, the National Sexual Assault Hotline saw a 20 percent spike in calls. During the second season, the hotline experienced a 40 percent higher number of calls than usual. Producers were stunned by the film’s reach.

“I think for the most part, most of these documentaries are putting together the pieces of a large puzzle, and you have no idea what the front of the box looks like yet,” Bryant said. “But the loudest and most impactful documentaries … [have] something that can connect to the viewer on a personal level, which makes all the difference.”

Similarly, the creative team behind “The New York Times Presents: Framing Britney Spears” were taken aback — and gratified — by the intense response to their documentary, which debuted last month on FX on Hulu. The film explored Spears’s rise to global pop icon, and the struggles that led to her being placed in her current conservatorship controlled by her father.

But the main discourse surrounding the film was the horror at the clips that showed how Spears was treated in the media as a teenager and young adult in the late 1990s through mid-2000s. Interviewers shamelessly asked about her breasts and whether she was a virgin. Respected newscasters seemed as if they were trying to make her cry on-air. When she was going through a difficult divorce and custody battle, she became a national punchline.

And there was so much the filmmakers didn’t include, like “horrible” jokes from “Family Guy” or comedian Sarah Silverman publicly roasting Spears and calling her children “adorable mistakes” at the 2007 MTV VMAs.

Seeing the coverage was a gut punch for some viewers, and they reacted strongly on social media. The filmmakers were “surprised and moved” by the reaction, said director Samantha Stark. “My biggest fear going into it was that people were going to interpret archival videos as a way to make fun of her and say she was crazy. I had a pessimistic viewpoint,” Stark said. “Then the opposite happened.”

While the current era’s more nuanced understanding of mental health may have helped in that case, the documentary led to another surprising result. Justin Timberlake, who dated Spears for three years and has long been criticized for how he used their breakup to boost his career, broke years of silence and apologized. “I know I failed,” he wrote in a message on social media, addressing both Spears and Janet Jackson, whom he essentially threw under the bus after their “wardrobe malfunction” incident during the 2004 Super Bowl halftime show.

The “Framing Britney Spears” team saw that, of course, though senior story editor Liz Day said she would rather focus on the wider implications of the film, and how it could spur conversations that move the culture forward.

“I’m less interested in Justin Timberlake putting out a statement on the Notes app or whatever than I am in normal people and civilians thinking about their own complicity,” said Day, adding that she has thought a lot about her own consumption of tabloids and reading Perez Hilton’s cruel blog posts when she was in college. “It made me rethink that behavior, and the appetite for those apparatuses to cover celebrities the way they did.”

Filmmakers agreed that just because their documentaries center on stories involving stars, the goal is for the audience to think about the bigger picture. Director Dan Reed, whose film “Leaving Neverland” premiered on HBO in March 2019, recalled the extreme backlash online from fans of Michael Jackson, whom Wade Robson and James Safechuck alleged sexually abused them when they were children. Yet at in-person screenings, Reed said, audiences were “bowled over by the candor and courage” of Robson and Safechuck “talking so explicitly about a topic that most people would rather avoid.”

The film “really sort of caused a cultural convulsion,” Reed said, and he heard from viewers who were very introspective about their previous reactions when the rumors about Jackson first surfaced, throughout his 1993 child sexual abuse case that was settled, and his 2005 molestation trial. (Jackson denied the charges until his death in 2009; when “Leaving Neverland” was released, his estate called it “a public lynching.”)

However, Reed said, the heart of the documentary was the phenomenon of how a powerful, trusted individual can harm children. “There were howls of protest from Jackson fans, but it was never really about Jackson,” he said, adding that he heard multiple stories of people citing “Leaving Neverland” as their motivation to speak out or confront their own abusers.

Ziering, of “Allen v. Farrow,” also emphasized that she would advise other documentarians that tying a film to a celebrity story isn’t the only way to get attention, as long as it’s an important topic that will strike a chord with viewers: “You don’t need a celebrity for people to hear and listen.”

Though that certainly doesn’t hurt, she added, “there’s a lot of change made without them, too.”

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