So here is what everyone knows about Hollywood: People there often behave badly—sometimes so badly they pay the ultimate price. In the past year alone, Cory Monteith, Chris Kelly of Kris Kross and Philip Seymour Hoffman all died of overdoses, and a slew of celebrities—Josh Brolin, Zac Efron, Trace Adkins, David Cassidy, Chris Brown, Lindsay Lohan (again!)—got treatment for drug or alcohol problems. Most shocking, Robin Williams, who had struggled with drug and alcohol addiction for decades, committed suicide in August after a brief trip to rehab intended to keep him on the straight and narrow. Go back a decade, and the list of addicts reads like a Hollywood who’s who. Of course by now it’s an old story with a few minor variations. Sometimes it’s barbiturates, sometimes barbiturates and alcohol, sometimes, as with Hoffman, heroin, though usually not in Hollywood (stars have access to better, legal stuff) and usually not at the age of 46 (heroin usually kills you sooner than that). Always there is the rehab that didn’t stick and the DUIs, the bar fights, the mug shots, the empty hotel room or apartment.

Addiction experts are quick to tell you addiction isn’t just a Hollywood problem; it’s a national problem. According to a 2012 national survey from the Substance Abuse and Mental Health Services Administration, there are an estimated 23.9 million addicts in America—one in 10 people over the age of 12, about one in four if you include nicotine addiction—and more people die from drug overdoses each year than from auto accidents. Even at the tony Malibu rehab centers that cater to A-list entertainers, celebrities constitute no more than 15 percent of the clients, though they account for 100 percent of the headlines, and for a few of them, including Lindsay Lohan, addiction has superseded performance. Being addicted is what she does. So some of the seeming Hollywood drug epidemic, experts say, is largely a product of visibility. TMZ doesn’t care about addicted truck drivers.

But only a part of it is visibility, because some things about Hollywood do seem to give rise to addiction—things that go all the way back to Wallace Reid, a silent-film star who died during morphine detox. Everyone seems to agree that the sources of addiction in the entertainment industry are complicated, with a whole lot of moving parts—a combination of biology, psychology and culture. In fact, there are so many moving parts, you could almost devise an algorithm for Hollywood addiction.

Before we get to that algorithm, let’s start at the beginning. When it comes to the course of addiction, it doesn’t make any difference if you’re a movie star or a plumber. In fact, most movie stars weren’t movie stars when they began using. (Look at Hoffman and Williams.) Constance Scharff, research director of the Cliffside Malibu rehab center and a recovering addict herself, says the vast majority of addicts were exposed to drugs and alcohol as children or teenagers—Lohan and Drew Barrymore, to name two—though they didn’t necessarily develop a dependency. The addiction can be, and usually is, dormant for years. Which, physically speaking, is where painkillers come in. One of the refrains of Hollywood addiction is that an actor or singer got hooked on painkillers. To the layman, it doesn’t make a whole lot of sense. What pain must they medicate for?

But experts say a lot of addiction is sparked by a legitimate medical reason and then escalates. Dr. Timothy Fong, director of the UCLA Addiction Medicine Clinic, recounts the story of a patient of his, a studio head, who dabbled in alcohol when she was young. Years later, when she had her wisdom teeth extracted, she got a Vicodin prescription for the pain. As Fong describes it, “She said, ‘Wow, I’ve never felt so good since I had alcohol back then. As soon as I had that first pill, I knew I was going to be off and running with this stuff.’ She blew through that first prescription, went back to the dentist, got another prescription—‘Oh, it’s so painful’—blew through that, then started asking around on the set. People started giving them to her because she was the studio head. The rumor mill got started, ‘Hey, she likes pills. You should bring her some pills. You might curry some favor.’ ” Indeed, the new formulations of these painkillers are so effective, the addictive process begins almost immediately, and when it does, it hits hard. Another doctor told me of patients who gobbled 50 to 60 Vicodin a day.

The proximate reason an addict takes drugs or drinks isn’t all that mysterious. It makes him feel good—hell, it makes him feel more than good. Fong describes another patient of his, who said, “Every time I drink alcohol, I have more confidence. I feel energized. I feel invincible. Every time I go out there when I’m not drinking, I’m double-checking everything. I’m anxious. I’m stumbling over my words.” The patient added, ironically, “I’m not as good as I normally am.” A former addict puts it more simply: “The voices in our heads quiet.” And we all realize that if it stayed that way, if the addict could continue in this euphoric state, there wouldn’t be a problem. The problem, says the recovering addict, is that “it ends badly. The story always ends badly.” It may take a few years, years in which the addict is constantly upping the ante as his body demands ever-higher dosages, but eventually the wheels come off. Another former addict states it more poetically: “Drugs put the soul to sleep.”

The reason we aren’t all wolfing down Vicodin, Percocet or OxyContin after we have our wisdom teeth extracted, or gulping down drinks or snorting lines, has a lot—roughly 50 percent for alcohol, 60 percent for cocaine and 70 percent for opiates—to do with genetics. Some people, perhaps 10 percent to 15 percent, according to Dr. Greg Skipper, director of medical health services at the Promises rehab center in Malibu, are predisposed to respond to drugs. It’s a function of brain chemistry. They just go off. They don’t have any choice.

But here’s where show business makes its appearance. If there are genetically endowed characteristics that make one more susceptible to addiction, some of these same characteristics make one more likely to be drawn to show business and even to succeed in it. In effect, Hollywood is a community of train wrecks waiting to happen. According to Dr. David Sack, chief executive of Promises and a psychiatrist, studies have shown a correlation between risk taking, which has a significant genetic component, and drug taking. “When you talk to actors,” he says, “they frequently talk about having to take risks with their work, to emote or behave in ways that are uncomfortable or dangerous to them.” A similar correlation exists between drug use and impulsivity, which psychiatrists define not as acting on the spur of the moment but as not valuing a future reward. Performing, in which you are constantly moving from one thing to the next, is one of the few professions that invites you to focus on the here and now. Most people can’t afford to do that.

Far more important than either of these is the high correlation between mental illness, which has a large genetic component, and addiction. Depression is so allied to addiction that doctors even have a name for the combination: dual diagnosis. Robin Williams suffered from deep depression. No one has studied the prevalence of mental illness specifically among entertainers any more than they have studied the prevalence of addiction in Hollywood, but, says Sack, “It is at least tempting to speculate that some of the mental disorders seem to have an unusual relationship to certain forms of creativity.” Performing artists may have abnormalities that travel with addiction. (Studies have shown that top athletes also exhibit a higher incidence of depression as well as a higher degree of addiction than ordinary people.)

Finally, there are those areas in which the effects of drugs are actually seen by performer-users to be advantageous in a way they would not necessarily be to people in other, more workaday professions. “A lot of guys come in and want to be on their A-game seven days a week—confident, funny, charming, social,” says Fong, because the industry celebrates and practically demands it. “The pathological thought there is, I must have it all.” The more common comment among entertainer-users is that drugs lift their inhibitions, which of course they do. “They wouldn’t have any street value if they didn’t,” says Fong. Some entertainers go so far as to say that drugs are what enable them to perform. As Fong sees it, people take drugs for only two reasons: the obvious one, which is to get high and experience a pleasurable time, and the less obvious one, which is to feel normal, “to take away the feelings of suffering.” He admits Hollywood puts a premium on both, which he believes is the reason addiction is so prevalent there. You can attempt to escape the pressures and insecurities, or you can attempt to control them. In short, you can try to medicate your way out of the occupational hazards of the industry. At least you can for a while.

Even at 66, Michael Des Barres looks and sounds like a rock-and-roller, which is what he was and is as the lead vocalist for half a dozen bands over the years. He is lean, chiseled, his gray hair short and stylishly coiffed, his accent British, and he is dressed in black from head to toe. Most people in entertainment won’t talk about addiction. Des Barres is one of the very few who will, and when he does, he knows whereof he speaks. “I’ve done every drug known to man or woman,” he says, “have had every sexual experience known to man or woman.” A good deal of that sybaritic lifestyle, he believes, is part of what he calls the “rock-and-roll mythology.” “How can you be a rock star if you’re not fucked-up? That’s like being a rock star with no music.” Des Barres wound up living within a heightened persona that obscured his person. “I was in a state of euphoria for a couple of years,” he says. “It felt perfect. I was fulfilling the rock-and-roll role.

But then came the reckoning. After a two-day binge that began with Jack Daniel’s and ended with Listerine, he looked in the mirror. “It didn’t look anything like me. Bloated. My makeup was running. My hair was coiled. I had that moment of clarity.” It was 1981. Des Barres quit drugs and alcohol cold, and he has been sober now for 33 years. He calls it a “divine thing.”

He will be the first to tell you, though, that it isn’t easy to be a sober rock star. “I was a leper. I went from being Aleister Crowley to Mr. Rogers overnight—with a better wardrobe.” Everyone, he says, encouraged drug taking, and that didn’t end with the cocaine-fueled 1970s and 1980s. No matter how much drugs are stigmatized elsewhere, they still have a cool factor in Hollywood and are part of the culture and community there. Fong says he has young patients, aspiring actors, who admit to going to parties and doing a line with a writer or director to create a connection and advance their careers. And that’s where Des Barres thinks Hollywood really is different from so much of the rest of America. It isn’t just the lack of stigma. It’s that Hollywood has enablers. Lots of them.

courtesy of Eliot Lee Hazel/RCA Records, Courtesy of Wikipedia, Alamy; AP Images, Everett Collection, Getty Images and Photoshop

It begins with doctors. “Star-fucking doctors are on every corner of Beverly Hills,” Des Barres says. Dr. Damon Raskin, who was a child TV actor and is now an internist at Cliffside Malibu, agrees. “I think there is a problem with doctors who suck up to celebrities in this town. ‘Oh, you need the Vicodin? I want to go to your concert.’ ” As a result, Raskin believes, “celebrities get worse medical care than you or myself.” Skipper remembers getting a call from a doctor friend who had been contacted by a member of a famous singer’s entourage in Atlanta who wanted a prescription for painkillers, even though the doctor had never seen the entertainer in his office. The doctor was tempted, and Skipper had to talk him out of writing it. After all, she was a star. The singer died of an overdose a month later.

But even worse enablers than doctors, Des Barres claims, are the managers and agents and entourage members, because they have a stake in the stars not going into rehab—in their continuing to work to earn money. They also have a stake in facilitating whatever the celebrity wants, because it is a way to hold on to their jobs. “Where are the people who say no?” Raskin asks. “They’re just afraid they’re going to get fired or be outcasts or not be part of the group.” So just about nobody says no. Indeed, one of the appurtenances of Hollywood addiction is the “sober companion,” who is hired by a manager to keep a star company while he or she performs. And the fact is, most entertainers can function well enough under the influence of drugs. “How is he going to do the tour and make $50 million?” Des Barres asks. “Oh, we need a sober companion! The whole notion of a sober companion is at odds with getting yourself straight through work and meditation and spiritual practices.” And when the tour or movie is over, the sober companion leaves. Such is drug addiction among the stars.

High up a hillside in Malibu, at the end of a winding road and across from the azure Pacific, is Cliffside Malibu, one of a handful of rehab centers with a wealthy clientele that includes occasional stars. It is quiet. It is always quiet at Cliffside. But Cliffside’s founder and CEO, Richard Taite, is anything but quiet. Tall and athletic, he is animated, especially when talking about addiction. Taite, 48, like so many in the rehab business, is a recovering addict himself. “From 12 to 32,” he says, “I never drew a sober breath. I never even fell asleep. I just passed out.” There were six-month runs, he remembers, when he would smoke an ounce of cocaine a day and eat a Big Mac once a week just to stay alive. Eventually, in 2003, he sobered up and decided to open his own Malibu mansion—he had made a fortune in the hospital billing and collection business—as a sober-living center. A year later he converted it into a rehab center.

As at Promises, Passages and other Malibu retreats, treatment at Cliffside doesn’t come cheap. Taite charges $73,000 a month for a private room, $58,000 for a semiprivate one, and the recommended stay is usually three to four months. (Like most upscale L.A. centers, it is nearly always filled.) He has had so many celebrities during the facility’s 10-year existence there is a sign warning patients when they might be in the line of sight of a paparazzo. It is a tough line to toe—the line between being a celebrity and being a patient. Being treated like ordinary folk may be necessary to address the underlying causes of the addiction, but stars are stars, and they don’t get a lot of tough love. Quite the contrary. They have their own network of therapists—four doctors, Taite says, who minister to nearly every big star. He adds, “If I told you the celebrities I see going in and out of my therapist’s office, you’d fall down the hill.” They have their own interventions, often conducted at a swanky Beverly Hills hotel, sometimes by Taite himself. They even have their own AA meetings, which are called “off-the-book,” where they can mingle with fellow stars.

You may think that with all these amenities, addicted celebrities would be lining up to enter rehab. But that’s another thing about Hollywood addiction: The stars are their own best enablers. Few—virtually none—seek help on their own. They have to be forced into rehab by family, friends or their lawyer, typically the one member of the support group who doesn’t work on commission. “I don’t think I’ve had an actual entertainer call me for themselves,” Taite says. “I’ve had the children, wives, girlfriends, cousins, brothers, sisters of every major movie star. I’m talking about the world’s biggest-grossing movie stars ever. I get them all calling. But not for themselves.” And why don’t the stars call to institutionalize themselves? Because of those enablers, Taite says. Nobody in Hollywood talks truth to power. Cliffside, like the other rehab centers, gets CEOs, athletes, high-powered attorneys and physicians. But Hollywood, he says, “is the only industry I’ve seen where you can be drunk or an addict, act badly and still have everybody kissing your ass.”

Taite subscribes to a theory of addiction devised by the psychologist James Prochaska. While it is by no means exclusive to Hollywood, it certainly has application there. According to Prochaska, most addiction is trauma related, and most of that trauma is rooted in childhood—in neglect, abuse or loss. “I’ve worked with thousands of addicts and alcoholics,” Constance Scharff, Cliffside’s research director, says, “and I know one person who said, ‘I had a really great childhood.’ ” Sack of Promises concurs, adding this Hollywood rider: Childhood abuse “may contribute to why performers are attracted to the creative arts, like maybe looking for redemption or acceptance or recognition they didn’t get in childhood.” Put another way, people who didn’t get attention as children may be more likely to become professional attention-getters, and the same emotional deficit may push them toward addiction. If anything, it is only worse for folks like Lohan and Efron, who may not even have had childhoods to speak of.

And here is the surprising thing. Although addiction almost always begins in childhood or adolescence, as many of us can attest from our own high school and college years of watching binge drinking, toking and even hard drug use, the vast majority of those abusers outgrow their misbehavior—“mature��� out of it, as some experts put it. The recklessness of youth, the imposition of responsibility, the constraints of life are transformative, which is why the frat-boy beer guzzlers seldom turn into alcoholics. But not in Hollywood, where recklessness is often rewarded, irresponsibility is actually encouraged and the only real constraint is being so wasted one isn’t able to work. That means addicted performers are always poised on the precipice. The industry’s infantilism puts them there.

All it takes is a trigger—some stress, such as a failed romance or a career setback— that reactivates the childhood trauma and leads to self-medication for relief. It doesn’t take much. So when you think of stars as train wrecks waiting to happen, you’re on the money. It doesn’t make any difference how long they’ve been clean when the trigger is pulled. Hoffman had been sober for 23 years. Then he wasn’t.

Kristen Johnston doesn’t buy it. She doesn’t buy that Hollywood is all that different from the rest of America. Johnston is the two-time Emmy–winning actress from 3rd Rock From the Sun who is as hilarious describing the indignities of her past addiction as she was playing an alien. She has written a best-selling book about it, titled Guts, which refers not only to what it took for her to recover but also to the time she almost lost hers by splitting her insides with drugs. She is now eight years sober and has been traveling the country talking to other addicts, none of them celebrities, though she has had celebrities call and e-mail her for advice and to offer thanks. She’s convinced Americans latch onto celebrity addicts as a way of pretending it’s just a Hollywood thing so they don’t have to face the truth.

But that doesn’t mean she believes performers don’t have some predispositions toward addiction, not because they are professional attention-getters but because they are professional targets. “You’re asked to be vulnerable and open and be all these different people and cry at the drop of a hat,” she says, “yet you’re also supposed to be able to survive when people tell you you’re ugly, you’re fat, they hate you. To survive without medication or help is very difficult.” Drugs, she admits, allowed her to mask her vulnerabilities—“to be large when I didn’t want to be.”

And Johnston says something else that other celebrity addicts echo: “Ambition is the best painkiller.” While this certainly isn’t true only of performers, it is more graphic with them. When they’re rising, they’re fueled by ambition. That is the drug—trying to be famous. Then, if they’re lucky, as Johnston was, they succeed. “All of a sudden, everything was free,” she recalls. “I had a huge home, I was in Los Angeles, and I just was lost. I had nothing else to work for.” And that is when her habit really kicked in.

Which leads to the algorithm. In varying degrees, genetic predisposition plus childhood trauma plus availability of drugs plus an emotional trigger plus encouragement or lack of discouragement is a pretty likely formula for addiction. Hollywood hits it on just about all cylinders. It is the disease of the lost in the industry of the lost. “We all have this hole inside of us,” Johnston says. “And we all try to fill it in some way. Some do it healthily. They write or they run or they have hobbies or whatever. Unfortunately, addicts find the easy road, which is really the hard road.” She says this isn’t just an addict thing. It’s a life thing. Johnston says, “Perhaps this process of filling the hole is what life is really about.” Though it may sound like psychobabble, the hole, of course, is that emptiness inside that can only be filled with identity—with knowing who you are. The trouble with performers, especially young performers, is that they are practically in the loss-of-identity business. They may be less likely to know who they are, less likely to be grounded, than most other people, which means the holes in Hollywood may be bigger than holes elsewhere—dug deeper by those childhood traumas, those vulnerabilities, insecurities and disappointments. The hole alienates you from other people, even as it alienates you from yourself. Johnston will tell you that is the pain the painkillers are really meant to dull: the pain of that gaping hole. (That is also why opiates are the Hollywood drug of choice.) “You are attempting to fill an unfillable hole,” Des Barres says. “There’s not enough water in the Pacific Ocean, not enough coke in all of Peru to satisfy it.” Not to put too fine a point on it, but while it is easy to caricature addicted celebs as being self-indulgent and out of control, it is much harder to see them, even somebody like Lindsay Lohan, as people who don’t have a clue who they are.

Johnston says that was the big change in her life: finding her identity. In addition to starring on the TV Land series The Exes, she now fills the emptiness by talking with addicts and lobbying for a sober high school in New York City. She is at peace and is confident she will stay that way. But experts say the relapse rate among entertainers is higher than the rate among non-entertainers, which is a very high rate itself—as high as 60 percent—and there are lots of reasons. There is the money that makes drugs accessible and the fawning that destigmatizes drug use, alongside the critical scrutiny of one’s work that attacks one’s vulnerabilities, the ongoing pressures of carrying a project that costs tens of millions of dollars and, perhaps above all, the enablement. Stars are more likely to leave rehab before the hole-filling process is complete. Although Richard Taite says he has never gotten a call from an agent or manager asking him to institutionalize an addicted star, he gets calls from them all the time begging him to release stars after a short stay. Too much is riding on them to keep them tucked away in Malibu.

One thing those who believe in Hollywood-addiction exceptionalism and those who don’t may agree on is that whatever else it is, Hollywood is America writ large. Everything there may be more dramatic, more excessive, more expensive, more exposed, but it is all just more. In the end, no matter how we try to deny it, the awful truth is that Hollywood is us, which means that though its addictions may be another form of entertainment for jaded Americans, they are really no different from our own. Take away Lindsay Lohan’s beauty and notoriety, and she’s just another pretty young girl trying to find herself. Take away Philip Seymour Hoffman’s enormous talent and recognition, and he’s just another middle-aged man in a desperate midlife crisis. Take away Robin Williams’s manic humor, and he’s just another depressive staring into the abyss.