The building, red bricked, colonnaded, crowned with a white cupola, sits on a grassy knoll in northwest Hinsdale. Unmarked, unremarkable, it barely registers as anything more than a garden-variety administrative headquarters of unknown provenance.

That isn’t to say that the decades-old property, situated on 223 acres in this Shangri-la of a western suburb of multimillion-dollar estates and country club splendor, has escaped notice over the years. The sight of teenage girls walking arm in arm in a nearby park, identically dressed in chaste ankle-length skirts, red scarves knotted around their necks, and modest Mary Janes, and of teen boys seemingly stamped out on a Wonder Bread assembly line—always in dark suits, white shirts, and ties—drew the occasional stare.

“Everyone kind of thought it was very strange. Like, what do they really do there?” says one longtime Hinsdale resident. “They always seemed very secretive.”

Then, in 2014, came a scandal. Some of those same red-scarfed girls accused Bill Gothard, the charismatic leader of the Institute in Basic Life Principles—the ultraconservative Christian organization operating out of that Hinsdale building—of inappropriately touching them. Gothard stepped down after an internal probe. But since then, 18 former staffers, interns, and volunteers have joined in a lawsuit accusing him of “sexually, physically, emotionally, spiritually, and/or psychologically [abusing]” them. In many cases, the plaintiffs were underage at the time and had been recruited to work for the organization by Gothard himself. The suit also takes on IBLP, accusing it of initially covering up Gothard’s actions, which the plaintiffs claim took place “over the course of several decades.”

Whatever the outcome of the case, the shroud of anonymity that once served as a kind of shield for IBLP against unwanted attention has been ripped away. The organization has even tried to make a fresh start by leaving Hinsdale and moving its headquarters to Texas. These days, as more becomes known about Gothard—of what the lawsuit alleges was his almost despotic control over his adherents and of the puritanical, idiosyncratic way of life he prescribed for them—shaken Hinsdale residents regard the benign-looking if somewhat abstruse manor down the street not as just another religious institution but as an organization with a disquieting appellation: the cult in their midst.

In the world beyond IBLP’s doors, news in 2014 that Gothard had resigned caused scarcely more than a ripple—other than in the tight circle of those who track fundamentalist Christian groups. That changed last year after an even bigger scandal, one involving TLC reality show star Josh Duggar. That May, it was revealed that the then-27-year-old Duggar, darling of the Christian right as head of the Family Research Council’s political action committee, had as a teen molested five girls, including four of his sisters.

Of the many unsettling details to emerge, one put IBLP squarely in the spotlight: When Duggar’s parents discovered the teenager’s transgressions, they sent him not to a traditional treatment center but to an IBLP facility in Little Rock, Arkansas. The Duggars had been involved with IBLP for nearly a quarter of a century; specifically, the family belonged to IBLP’s homeschooling arm, the Advanced Training Institute.

Suddenly, a keen interest developed in the brick building in Hinsdale. Just what exactly was that place, and what was going on there?

“I think that the community at large didn’t even really realize that it was there,” says Don Veinot, president of Midwest Christian Outreach, an evangelical group based in Wonder Lake, Illinois, that investigates cults and spiritually oppressive groups. “Unless you have some sort of direct interaction with someone there, you’re not going to think very much about it.”

On IBLP’s website, the nonprofit organization describes itself as “dedicated to giving individuals, families, churches, schools, communities, governments, and businesses clear instruction and training on how to find success by following God’s principles found in Scripture.” The group pushes an authoritarian, patriarchal theology conceived, developed, and thundered from the pulpit by Gothard over the years.

The approach has resonated with conservative evangelicals to the tune of millions of followers, most of whom have become involved with the organization through seminars put on by Gothard around the country. On its website, IBLP boasts that 2.5 million people have attended such events over its five-plus decades. Many of its adherents have enlisted their children in the homeschooling program, serviced by more than a dozen ATI centers sprinkled around the nation and abroad, including in Hinsdale. IBLP’s supporters over the years—many of whom continue to defend it—include such high-profile conservative stalwarts as Mike Huckabee, Sarah Palin, and Rick Perry. (See “IBLP’s Big-Name Supporters,” below.)

The lawsuit, however, alleges a less heavenly place for the plaintiffs, who worked at the Hinsdale headquarters. At its peak, in the 1990s and early 2000s, IBLP had 200 to 300 staffers there, living several at a time in nearby houses or a dormitory-style apartment building the organization owned. Gothard, the lawsuit contends, acted as “the boss, the landlord, and the controller of all aspects of their lives.” He kept his “victims blamed, shamed, silent, compliant,” the suit alleges, and “cut off from the normal world entirely.” (Gothard’s attorney wouldn’t comment on specific allegations in the lawsuit but did say, “This is about an underlying agenda.” A lawyer for IBLP declined to be interviewed for this story. The defendants are seeking to have the suit dismissed on technical grounds, primarily that the statute of limitations on the allegations has passed.)

“You never think you are in a cult when you are in a cult,” Micah J. Murray, who was a student in the ATI program and later worked for IBLP in the mid-2000s, wrote on his website. “We talked about how it was a cult, joking at first. … But as I spiraled closer and closer to the center, the realization began to sink in. The jokes became real.”

The seeds of Gothard’s rise to power were sown not far from where he would build and rule his empire. He was born in Hinsdale, in fact, the son of William Gothard Sr., executive director at Gideons International, the evangelical ministry known for leaving Bibles in hotel rooms. The third of six children, Gothard was, by his teenage years, deeply religious. According to his bio on the IBLP website, he “began working with inner-city gangs in Chicago” and “families in crisis” to help them “make wise choices.”

The organization that would become IBLP derived from a master’s thesis Gothard wrote in 1961 while at Wheaton College. Gothard set up a program called Campus Teams, run out of his La Grange home, for resolving conflicts between teens and their families. In 1974, the fledgling organization changed its name to the Institute in Basic Youth Conflicts. In the years that followed, it would expand far beyond teen issues, prompting yet another name change, to the Institute in Basic Life Principles, in 1989.

According to the lawsuit, IBLP developed an extravagantly detailed “purity culture” that provided guidelines on “marriage, women, children, medicine, and ways to take back and fix the nation.” Its philosophy included everything from the general (what children should study, from kindergarten through high school) to the granular (exactly how young men and women should dress, style their hair, and comport themselves to avoid attracting sinful attention). ATI’s homeschooling curriculum consists of 54 “wisdom booklets,” which teach subjects including geography, math, science, law, and government, tying each lesson to Gothard’s interpretation of a corresponding biblical passage.

Virtually all of IBLP’s teachings are viewed through the prism of male superiority and female obedience. In marriage, for example, the husband is the undisputed leader of the family and his word is final. Elsewhere, women defer to men in almost every circumstance, on almost every level, including in the workplace. This belief system, the lawsuit says, “considers women to primarily exist for the purposes of producing children, caring for the men, and rearing the children. Females in the patriarchal movement are discouraged from attaining higher education of any kind and are told that their sole purpose is to marry a man within the movement.”

Strict, sometimes draconian, moral codes find purchase in virtually all fundamentalist Christian groups. In the case of IBLP, however, some of the tenets seem downright bizarre: Cabbage Patch Kids are idolatrous, syncopated music is “the antithesis of what God desires in the life of a Christian,” blue jeans are ungodly, circumcised men are morally purer than uncircumcised men. One IBLP article suggests that failing to “render to the Lord” can lead to miscarriage. Another, titled “How Are Eyelids Used for Seductive Purposes?,” rails against the “whoredom” of the female wink: Such an act by “an attractive, but immoral woman” can be used to “communicate lustful desires and sensual entrapments.”

IBLP’s other teachings could be straight out of Footloose. Rock music, even Christian rock, is unthinkable. Dancing, of course, is out of the question. So, too, are television, movies, romance novels, and drinking. Boys are not allowed to talk to girls in the lobby of the IBLP headquarters. Dating is forbidden. Instead, a boy and girl whose fathers believe might make a good pair must follow a highly circumscribed courting ritual, every aspect of which is monitored by their parents.

When it comes to appearance, girls in particular face a long list of rules. For instance, they must avoid an “eye-trap”—that is, anything that draws attention to their bodies. “So it could be a neckline that shows anything other than your collarbone, a necklace that was longer than 16 inches,” explains Charis Barker, one of the plaintiffs in the case, who was involved with IBLP from 1986 to 2000, first as a child homeschooled under its tenets, then as a staffer.

The lawsuit claims that Gothard, who holds no medical degree, provided therapeutic counseling according to his own whims. One of its most dramatic allegations involves a young woman on staff who asked for guidance on dealing with the emotional fallout of having been raped at age 11 (by someone not in the organization). The suit alleges Gothard discouraged the staffer from seeking outside psychological treatment. “No, a professional counselor would ruin you and all your potential to serve the Lord,” the lawsuit alleges Gothard told the woman. “Professional counselors do not know how to work with abused girls, only I do.” Gothard decided not to report the rape to authorities based on the flip of a coin, the suit claims.

Says Gretchen Wilkinson, a plaintiff in the suit who was an IBLP adherent as a youth: “My perception of God was fire and brimstone—that if you stepped outside the line, you would go through what Sodom and Gomorrah went through. That God would rain his fire down on you.” Real-world consequences at IBLP included scoldings, intense counseling, demotions, and even being kicked out altogether.

“It’s a culture of fear, is what it is,” says Veinot, who wrote a book about Gothard and IBLP. “If you [follow] these rules, you make God happy and thereby will be protected. If you violate the rules, then you will be punished: Your car will break down and your washing machine won’t work and your kids will rebel.” The charismatic leader, the authoritarian control, the isolation of members, the severe punishments, the demand for absolute and blind loyalty—all those elements outlined in the lawsuit add up to IBLP being “cult-like,” he says.

Nonetheless, the strict approach found an enormous audience. Within a few years of his organization’s founding, Gothard was packing 10,000-seat conference centers, and IBLP was raking in millions in revenue from seminar fees, book sales, and donations. In time, it would expand beyond homeschooling and seminars to a wide variety of programs, including its Air Land Emergency Rescue Team, which trains young men “to aid in disaster relief,” according to the organization’s website. Training centers for various programs opened across the country in Alabama, Arizona, Indiana, Michigan, Oklahoma, Tennessee, and Texas and overseas in New Zealand and Romania.

Gothard himself has led a modest life—at least on the surface. He’s never been married. He drove a plain car. In 1973, he claimed to take only $600 a month in salary. But there were trappings of big money: In 1979, IBLP, which already owned a passenger turboprop, purchased a Learjet, which Gothard used to fly to seminars and meetings.

IBLP poured some of its income into property. In addition to the headquarters campus in Hinsdale, it bought a building in neighboring Oak Brook. As the organization grew and staff increased in the 1990s, it purchased several modest houses in Oak Brook and an apartment building there that it used as a 25-person dormitory.

The expansion efforts weren’t always welcome. When IBLP sought to add more buildings in Hinsdale and Oak Brook—including six office and maintenance buildings, 66 houses, and a 337-room hotel for visiting guests—neighborhood groups, disturbed by Gothard’s increasingly controversial national reputation, filed suit to stop the proposed developments. “He’s narcissistic,” a resident told the Chicago Tribune in 1992. “He thinks he’s God.” IBLP eventually dropped those plans.

As for other dealings with Hinsdale, IBLP was tolerated as an odd but mostly nonthreatening presence, says a former village official. “They were never doing anything wrong,” she says. “The police were never called.” At times, in fact, IBLP proved to be generous: Hinsdale officials accepted its offer to print the village’s newsletter free at the organization’s printing facility.

Few residents were aware of a 1980s sex scandal involving Gothard’s brother that threatened to take the entire empire down. Steve Gothard, who worked for the organization at the time, publicly admitted to having a number of affairs with female staffers at a 3,000-acre retreat center the group owned in Michigan. Bill Gothard was accused by other staffers of dragging his feet in reprimanding his sibling and was forced by the organization’s officials to step down. He was reinstated after a few weeks, however, and emerged stronger and more in control than ever.

By the time Gretchen Wilkinson began working at IBLP’s headquarters in the early 1990s, that scandal had faded and Gothard stood as a towering, deeply revered figure. “I was in awe of him,” says Wilkinson, whose family adhered to his teachings. “I was told by my parents that I was alive because of him—that they weren’t going to have any more children and they chose to follow God’s principles and follow what Gothard laid down, and as a result I was born.” In short, she says, “I was told I owed my life to Bill Gothard.”

Whatever problems Gothard might have run into, whatever criticisms his rigid philosophy may have inspired, few would deny the force of his personality. With a high forehead and roundish face, he bears a resemblance to Dennis Hopper. He wore his dark hair, which has receded in his twilight years (he is now 81), parted, and he was almost never seen in anything other than a dark suit. So worshiped was he that one plaintiff likened him to the pope.

Wilkinson first encountered Gothard at a seminar in Knoxville, Tennessee, in 1992. She was 16. “From the very first time I met Bill Gothard, he was very affixed on me,” she says. “I remember he held my hand and wouldn’t let go, looking me in my eyes and telling me how my eyes were my soul, and just that I had a beautiful smile.”

He implored her to come work at the headquarters in Hinsdale. “He wanted me to leave with him right then,” she says. To her, it was an unfathomable offer—and an honor: “The fact that he would pick out one little minion to be graced with his presence was huge.” Her parents balked at first, she says, but within a week flew her to Chicago to join the IBLP staff.

Rachel Frost tells a similar story. She was to perform at an event in Knoxville with the IBLP’s orchestra and was searching for her flute when Gothard introduced himself. “He just came up to me, tapped me on the shoulder, and gave me a once-over,” Frost recalls. She was thrilled to find herself in his presence. “It was something you dreamed about—meeting Bill Gothard in the flesh. It was like the president of the United States tapping you on the shoulder. You don’t expect it. In our world, the conservative, homeschool world, he was everything. There were hundreds of people there waiting to touch the hem of his garment.”

She says Gothard asked her if she had ever considered working for the IBLP. She would love to, she told him, but was only 15. Gothard was not dissuaded. He approached her parents. “He was like, ‘I need her [in Hinsdale] now,’ ” says Frost. “Even they were taken aback.” But they agreed. “It was a huge thing for the whole family.”

Within weeks, she was on a plane—Gothard had offered to pay for the ticket—installed in an apartment, and given a job as one of his personal secretaries. Two years later, she was traveling with Gothard on international trips and had become a prominent face and voice in IBLP marketing materials.

Wilkinson, likewise, found herself singled out by Gothard for special treatment. She was invited by him to join a group he led that traveled to Australia and New Zealand. Some favorites were granted the unthinkable privilege of wearing red nail polish; others were allowed to wear heels.

It wasn’t long, though, before both women, and others like them, began to reassess the man, the organization, and what they had gotten themselves into. For Frost, the moment came at a staff lunch. Having been invited by Gothard to sit at his table, she felt his foot nudge hers. She was mortified. “I was thinking, Oh, that was totally a mistake. It was my mistake,” she recalls. “Then the next few times, [his foot] would be going further up the calf.”

She felt shaken, she says, but couldn’t bring herself to believe that Gothard had nefarious intentions. So she kept quiet about the incident. “I felt I needed to protect his reputation because I know this is not probably what he means to do, and this is my evil mind thinking that this is something more. I’ve got to keep my legs back, because maybe I am sending him signals, you know?”

Another young staffer, Charis Barker, who worked in Hinsdale from 1999 to 2000, recalls uneasy encounters with Gothard. “He would invite me to sit at the head table every time we had a meal together, and then, if it was the evening, he would invite me to come back up to his office. He’d want me to sit on his couch with him, and he would ask me to confess sins and any relationships I’d had with boys, things like that.”

Dining at Gothard’s table, she “kept bumping his feet,” she says. “So I would sit with my feet wrapped around the legs of the chair.” But sitting on his office couch during one-on-one counseling sessions was more complicated: “You couldn’t get away from this because [his foot] kept coming up your legs. And that got really uncomfortable.”

Like many of the young girls recruited to work for IBLP in Hinsdale, Barker, whose parents enrolled her in the ATI homeschooling program when she was 6, had grown up sheltered. “I just remember a massive amount of confusion [after the Gothard encounters], because my parents had kept us from any type of sexual knowledge at all,” she says. “I only knew what sex was because I had read the encyclopedia.”

In Frost’s case, the most disturbing incident came one night while she was riding in a car with Gothard. At one point, the lawsuit alleges, he “suddenly leaned forward and roughly grabbed almost all of her hair close to the nape of her neck in his fist and whispered through clenched teeth, ‘I love your hair.’ ”

Says Frost: “It was just a shock to me that, like, OK, I can’t explain this away anymore. I remember being in this turmoil, wanting to talk about this with somebody, because I totally felt like he crossed a line there. But you just do not talk against God’s anointed, you know.”

In Wilkinson’s case, the behavior escalated beyond foot rubbing and inappropriate conversation. One time when she was alone in Gothard’s office, the suit alleges, he placed “his hands on [her] breasts and on her thighs—up to her genitals, while she was clothed.”

The lawsuit describes a similar experience of another young woman, one who worked at the Hinsdale headquarters more recently, in 2012. During a late-night Bible study session in Gothard’s office, the suit alleges, the IBLP leader rubbed the staffer’s thighs “very close to her vaginal area.” She was 15 at the time.

The experiences of many of these young women lay dormant for years. Then, in July 2011, a group of IBLP and ATI alumni, concerned about whispers they had been hearing, created a website called Recovering Grace. The intention was for people to share information about how their lives had been negatively affected by the teachings of Gothard. In 2012, the site published “Lizzie’s Story.” Written by a woman who had worked at the Hinsdale headquarters as a 17-year-old, it describes several instances during conference trips in which she felt Gothard had touched her inappropriately.

The tale resonated with Wilkinson, now 40. She had struggled to heal emotionally after leaving IBLP. Her experiences there had affected virtually every aspect of her life, from her relationships with men and her own family to her self-esteem. She says she twice tried to kill herself before finally getting help. When she read “Lizzie’s Story” and others that began popping up on Recovering Grace, she “fell apart”: “Everything I had held together—it’s like a dam broke.”

Today things are better for Wilkinson, a florist and mother of two in Virginia. “I have been blessed with a very understanding, very supportive husband who has allowed me to grieve and live and to rant and to rave,” she says. “He’s allowed me to explore my belief, my nonbelief, my hurt, my pains. I still mourn what I’ve lost, but I also realize it doesn’t define who I am now.”

Wilkinson posted her own story on the website—a tale that, in turn, had an impact on Frost. Now 39 and a fitness instructor in Minnesota, Frost had tried to repress memories of her time at IBLP. “Someone texted me, ‘Hey, have you seen this story? Do you know this girl?’ I read it, and I just bawled. It was almost like watching a movie. All these thoughts and all these memories and everything were just becoming so clear.”

With accusations surfacing—including a police report made by one accuser—IBLP initiated an internal investigation of Gothard in 2014, and he subsequently stepped down. The probe’s conclusions, later published on IBLP’s website, stated that “no criminal activity has been discovered” but Gothard “acted in an inappropriate manner.” In the only public statement he has made about the allegations, Gothard acknowledged that he had “crossed the boundaries of discretion … and violated a trust.” But he drew a line: “I do want to state that I have never kissed a girl nor have I touched a girl immorally or with sexual intent.”

In October 2015, five women initiated the lawsuit against Gothard and IBLP, and since then 13 others have joined as plaintiffs. Frost, Wilkinson, and Barker are among those suing.

Lawyers for the women accuse the organization of trying to cut and run by transferring its operations to Big Sandy, Texas. IBLP calls the move a cost-saving measure. Its most recent tax filing shows that the once-flush group spent nearly $5 million more than it took in during 2014. “The organization, though still worth an estimated $100 million, appears to be in a dramatic financial crisis due to declining donations, decreased sales, and high expenses,” the lawsuit states.

One loyal group of adherents, a West Virginia family with its own ministry, seems unfazed. On its website, under the headline “Texas Ho!,” the family wrote: “While this brings a chapter of IBLP’s history to a close, the vision of introducing people to Jesus Christ and providing families, churches, businesses, and nations with Biblical training on how to find true success in life remains unchanged. The Lord has worked mightily in the past and we are excited about what He has for the future.”

On a recent afternoon at the colonnaded building in Hinsdale, the future did not look exciting. More like abandoned. No girls in ankle-length skirts floated in and out or strolled in the nearby park; no boys in dark suits and crisp white shirts tended the gardens or climbed on shuttle buses to destinations unknown. The parking lot stood empty. The normally well-manicured lawn looked a little forlorn. Even the sign that had once provided the lone hint of what the building represented was gone.

On this day, in this light, it was just another building.