A hiss pierces the air as music fans wait in line outside the Brooklyn (N.Y.) Bowl in Williamsburg. Across the street from the venue, a man stoops over his tank, inflating balloons and passing them to his associates by the fistful. He shuts off the valve and surveys the scene. Deciding his handlers are moving too slowly, he picks up the tank and slams it against the corner of the warehouse, sending a shrieking echo into the night. "I don't see you working fast enough!" he yells. Then he unleashes an exploding stream of gas into the air, rapidly firing left and right and cackling devilishly like a kid with a water pistol.The balloon man, who asks not to be named, has a shaved head and a New England accent. He's the leader of the Boston ring of the "Nitrous Mafia"—a term invented by critics of his business. The Disco Biscuits' performance is about to start. And the fans in line are high from his laughing gas."Fatty whippets!" yell the balloon man's eight or nine dealers, holding balloon clusters high in the air. Some of the dealers are locals, contracted out for the night, while the rest hail from Massachusetts and Rhode Island. When a police car is seen from a distance, a trio of spotters yells, "Six-Up"—a warning to keep cool. Selling nitrous oxide for the purpose of getting high is illegal, but the club's bouncers don't seem to mind the huffing. "The security here is cool," says a dealer named Chrystal, a single mother who is dating the Boston capo, whom we'll call Dmitri.Throughout the year, the Nitrous Mafia travels from state to state, selling balloons at concert sites. The scene in Williamsburg is only a small preview of what happens in summer, when the outdoor-festival season kicks into gear. During these campground events, which last two to four days, the Mafia, which is divided into two rings, based in Boston and Philadelphia, can burn through hundreds of nitrous tanks. With the ability to fill up to 350 balloons per tank, which they sell for $5 and $10, they can bank more than $300,000 per festival, minus expenses. Year after year, security guards at these events attempt to crack down on the illicit business, but, in most cases, they're outmatched by a phalanx of menacing gas dealers who have little regard for unarmed concert personnel.And for some musicians and their fans, the illicit trade is a bummer. "It has a negative impact on the entire scene," says Don Richards, the tour manager for Umphrey's McGee, ranked the #4 jam band in a recent Rolling Stone poll. "It's a very controlling group, to the point where I've seen people get beat up.""It's something that should be left to the dentist's office," says Josh Clark, the lead vocalist for the San Francisco–based jam band Tea Leaf Green.But Dmitri, who has been in and out of jail on multiple occasions, defends the operation. "You don't want it, don't buy it," he says. "We're not forcing you to do anything. You can keep walking." He lives in Rhode Island, but he and his associates will crash at his New York apartment tonight. Business has been slow, he says, and each worker will probably clear only $300 for this show. But he hopes things will pick up during the summer. When asked, he denies his crew is an organized crime ring. "There is no Nitrous Mafia," he says.It is inevitable. At many summer music festivals around the U.S., from Maine to Miami Beach, the opening chords eventually give way to the whistling of tanks. In parking lots and alleyways. In mountain crevasses and open fields. At popular campsite events like All Good, in Masontown, W.Va.; Bonnaroo, in Manchester, Tenn.; and Gathering of the Vibes, in Bridgeport, Conn.. the Nitrous Mafia is there."You hear the hiss of that tank, and you know you're approaching a shady corner," says Clark, of Tea Leaf Green. "When I'm near it, I'm always afraid I'll wind up in some blurb for a music magazine."Nitrous is called "hippie crack" because of its addictive qualities. Every morning, the festival campgrounds are riddled with balloons, "like bullet shells on a battlefield," says a fan. Unlike traditional drugs that have long-lasting effects and can carry a fan through a concert, the high from N20 is cheap and quick. After that, it's often back to the end of the tank line for another round. "It's an instant rush of pure euphoria, but it only lasts for 30 seconds or a minute, and then you want it back," says Justin Heller, a fan who owns his own biodiesel company. He no longer does balloons, but remembers the days of buying 15 in a row. "You don't think about your money—you're just, like, 'I want that again.'"But some jam-band fans complain that the nitrous racket is harshing their idyllic pursuit, recalling a time when laughing gas was part of the hippie ethos."It's a sore on the scene," says Kevin Calabro, a Brooklyn-based publicist for jam bands. "It's been taken over by dirtbags and Mafia punks. It used to be, in the old Dead days, that some hippies got their hands on a tank, and it was a mellow and loose kind of thing. Now it's become some dirty-ass shit that's too easy to abuse.""These people are evil," says Don Bryant, a retired Army captain and emergency medical technician who also vends T-shirts at shows. During a recent Bonnaroo festival, he says, "One guy with a $5 balloon of nitrous came crashing through my booth, being chased by a guy with a knife. He almost took out my daughter, who was a little baby."Scott Percival, a Boston police officer who serves as a security guard for the Gathering of the Vibes, says he was once offered $10,000 by a dealer to look the other way, and recalls stumbling onto one beaten-up and unconscious seller lying in the parking lot, pockets empty. "He was selling nitrous, and the other guys came in and took him out. It happens all the time," he says. "It's a big-time problem," echoes Dennis O'Connor, a Hartford police officer who confiscated 25 tanks outside a Phish show last year.Forced to play a four-day game of Whac-a-Mole, the guards at festivals move in on one dealer with a tank, and another pops up on the other side of the park. "It's frighteningly organized," says Richards, of Umphrey's McGee. "They know how to hide and get out of a scene very quickly. I've witnessed them set up for 10 minutes and make thousands of dollars selling balloons. And as soon as security and police converge on a location, they're gone. They disappear. They think things out very clearly about how they're going to escape certain situations."For concertgoers, the most dangerous risk of nitrous is the potential for users to pass out and hit the pavement. "I've watched so many young people crack their heads and face open that I have personally stopped providing emergency first aid," says Bryant, the EMT. "I've seen them fall and bust out all their teeth. I've seen them fall and hit glass. They fall like flies all over the place. It's a sad thing." Pointing to a scar on his chin, one fan elaborates on a recent nitrous experience in Pittsburgh: "My last thoughts were 'I need to sit down right now,' and the next thing I know, I wake up in a pool of blood with five people surrounding me."Last year, a festivalgoer turned up dead at Gathering of the Vibes. Within days, the jam-band blogosphere lit up, hurling accusations at the Nitrous Mafia, with claims that the victim had been beaten with a tank, sprayed with gas, and burned alive. Weeks later, a toxicology report ruled that he'd died from a simple drug overdose, but the episode was still a black eye for festival promoter Ken Hays, who came under fire from Bridgeport authorities for failure to control the scene. Despite confiscating about 100 tanks, the security guards at Vibes proved no match for the gas mob."We were overrun," admits a security executive. "We weren't counting on the amount of nitrous they would bring in." Kevin O'Brien, the marketing director of last year's Vibes, says he was offered a bribe of thousands of dollars by a nitrous dealer named "Crispy." The firm Security Operations Consultants, one of five security companies that worked the festival, was the subject of an FBI investigation, allegedly for failing to turn over tanks and drugs taken from concertgoers to the police.Despite the scandal, Hays eventually won his months-long battle to bring his festival, born out of Jerry Garcia's death, back to Bridgeport. He has instituted a zero-tolerance balloon ban this year, and is working with the Bridgeport police force and City Council to make the possession of nitrous oxide illegal in Bridgeport's public parks. He says he hopes legislation will be enacted before the festival, though the parks commissioner isn't sure that it can be enforced.The guards aren't sure, either. "People just don't know what's going on," says Marshall Rodriguez, the owner of the security firm in charge of the backstage area of Vibes. (Indeed, two cops interviewed for this story referred to the gas as "helium.") A few years ago, Rodriguez almost shut down his business after one of his guards was pistol-whipped and another threatened at knifepoint by nitrous dealers at a festival in West Virginia. "You got a group of guys who are coming in...[making] money they're willing to go to great lengths to protect, even if it means hurting somebody, even if it means hurting security," he said. "It's just starting to get out of control."Inside a dimly lit roadhouse in Nowheresville, Mass., "Sean" has agreed to talk about his time as a member of the Nitrous Mafia, provided his real name isn't used and the venue isn't named. Twenty-four years old, Sean sips a bottle of lager and speaks in a raspy whisper. His dreadlocked hair spills over his Grateful Dead visor and down his back, and a green bandanna hangs loosely from his neck. In a few minutes, he will take the stage as a guitarist for one of the bands playing tonight. A self-described hippie, he was considered a valuable member of the Mafia because he blended in at festivals.Sean explains that the Boston ring of the Nitrous Mafia is made up of about 16 members split into two units, with the entire operation run by the Rhode Island kingpin, Dmitri—the guy with the New England accent slamming the tank against the wall in Williamsburg. With the help of false paperwork, gang members fill up tanks of various sizes at a local nitrous shop, a kitchen-supply store called New England Fountain, located in Burlington, Mass. (The store's owner, Paul Abramo, says he's aware that some of his customers might be illegal dealers, but it's impossible to regulate: "We try to make sure they're a business, but beyond that, it's really out of our control.")During festival season, gang members are able to fill 40 nitrous tanks at a time for $75 each, says Sean. During his employment, the two Boston crews would duel every night to see who could make more money. "It was almost like a game to us," he says. Members of each unit split 30 percent of the profits while the remaining 70 percent was funneled back to their bosses.The Philadelphia ring is larger and split into several sub-crews who know each other but operate independently, says Sean. "The Philly guys are more reckless," he says, and more prone to violence and intimidation. "They operate without a code of honor. They were the first kids I saw bringing guns to the lots and putting fuckin' shit to people's heads." The Philadelphia don, who owns his own nitrous supply store and has several workers underneath him, is less apt to show up at festivals himself, says Sean. "He's a fucking nut job," he adds, noting that even Dmitri is deferential to him.Sean, who admits that he has been in and out of jail for drug charges, was recruited into the Mafia last year during a time when he had no money and no food and was struggling to see his favorite bands. During All Good, a mob acquaintance offered to pay him to go on balloon runs. "Next thing I know, I made $60 in 40 minutes," Sean recalls. "It was big money. Eventually, I started making $900 a weekend." He was employed for a four-month period, during which time he spent nearly every day on the road with his colleagues, living in hotels and U-Haul vans. He fell in love with the lifestyle because of the instant respect that came with being a balloon seller. Girls would remove their tops in front of him just for a huff. "It worked all the fuckin' time," he says. Fans would drop $200 in three hours at his tank.As a full-time Mafia member, Sean was known for his crafty methods of sneaking tanks past security guards. "I liked to store them inside box springs," he says. "We'd strip out the bottom and stash six cans inside. Then we'd lay it back down, put a mattress and blanket on it, and make the bed. Security would open the back of the U-Haul, see a made bed, close the door, and let us ride right on through." On other occasions, he'd rip out the floor panels of vans and stash the tanks, always spray-painted black, in the undercarriage. "We'd laugh our way through every check point with three fuckin' tanks underneath the car," he says. A colleague of his—a woman with a young child—would often traffic tanks hidden under blankets in her baby stroller.During festival season, the Boston and Philadelphia crews band together, operating in higher numbers, assisted by a recruited class of lower-level minions who aren't card-carrying members of the Nitrous Mafia but are eager to make a summer buck. They're often ex-cons—"crack dealers and dirtbag kids straight outta jail," says Sean—who like the idea of selling balloons to rich kids while inhaling all the nitrous balloons they want for free. The full-time workers handle the money and oversee the stash houses, while the younger kids serve as lookouts and runners, communicating with one another with verbal signs and cell-phone texts. "It's usually six guys to a tank," explains Sean. "One guy strappin', one guy fillin', one guy takin' money, then usually three lookouts spread out in a triangle about 20 feet in each direction watching for security."After leaving on bad terms—he won't go into detail—Sean says he wished he had never got caught up with the mob. "I realize the demons associated with it," he says. "They're really ruining the hippie scene." Then he leaves the table, grabs his guitar, and takes the stage, launching into the opening stanza of a blues song.Nitrous oxide has been around as long as jam bands themselves. One brief scene in The Grateful Dead Movie, a documentary about a series of San Francisco shows in 1974, includes a scene where nitrous is consumed with an octopus-like hose. "It was easy to come by, and part of the party," says songwriter and producer David Gans, who collaborated with Jerry Garcia. During the 1970s, the gas was sometimes supplied at recording studios. By the mid-'80s, the tanks began appearing on "Shakedown Street," the name for the public marketplace that Deadheads ginned up at concert venues to finance their continuous touring. By the end of the decade, nitrous was standard fare.But many Deadheads were turned off by the tanks from the onset, and began referring to the dealers as "tour rats" who made money off the mother ship. "They saw the nitrous vendors as people from outside of the subculture sucking profits out of the scene," says sociologist Rebecca Adams, a professor and associate provost at the University of North Carolina at Greensboro. "They would sell the nitrous and then disappear, without spending money on tour. They were profiteers, or what Dead Heads called corporate vendors." Garcia was aware of the problem, says Gans, "but he was pathologically unable to take control and responsibility."At the turn of the century, following the death of Garcia and the expansion of jam-band culture, Shakedown Streets along the East Coast began to attract nitrous dealers in greater numbers, and people who looked less like Phish fans. "I began noticing that all the people selling balloons weren't nice hippie kids trying to go from show to show," says fan Justin Heller. "It became clear that they were a bunch of thugs trying to make money.""They're sketchy," says one fan. "They're shit," says another. One fan cuts right to the point: "These guys don't even know who Jerry Garcia is, and they never will." Other vendors began complaining that nitrous sales drove down their T-shirt and jewelry businesses. "Nitrous straight robs the pockets of the other workers," says Sean, the ex-member of the Nitrous Mafia. "Everybody's fuckin' broke 'cause they dropped every dollar they had on nitrous."This new class of gas dealers seemed to come almost exclusively from Philadelphia, where nitrous was easy to purchase. By 2003, the gas business had outgrown Shakedown Street and had crept onto street corners. Outside some concerts, tanks were stationed several feet apart from each other. Eventually, turf wars started breaking out, leading to intimidation and violence. Stronger nitrous dealers would ask lower-level merchants to hand over their tanks—or risk the consequences."If you start working Shakedown next to a bunch of the mob kids, and you try running your own tank there, you're gonna get that tank taken from you and it's gonna become theirs, unless you're paying them off," says Sean. "They do not let you work around them without being one of them. And that's where the Mafia aspect really came around."One fan says he was beaten up two years ago at New York's Jones Beach because a dealer thought he'd stolen a balloon. Last year at Vibes (where a portion of the park has been dubbed "Nitrous Alley"), a fan says he saw a dealer smash his tank on a man's head. At a Phish show last year in Portland, Maine, a fan watched a parking attendant get pummeled. Knives and bats were sneaked into lots. "I straight-up saw a Nitrous Mafia guy hit a cop's face in with a tank," says a man who recently attended All Good, a mountainous festival venue where gas is inhaled inside a deep gorge called "Wookie Nitrous Cave." "Nobody fucks with those fuckers," says a tattoo artist who goes by the name PeaT.Clark, of Tea Leaf Green, doesn't get why his fans are drawn to the stuff: "There are certain drugs that enhance the concert experience—a little doobie here, or some mushrooms there," he says. "But I don't see how nitrous enhances the concert experience. With other drugs, you can dance. With nitrous, you slump onto a car and disappear until it's time for the next balloon. They don't call it 'hippie crack' for nothing."The U.S. Drug Enforcement Agency doesn't consider nitrous a controlled substance and doesn't regulate it. Instead, it's monitored by the Food and Drug Administration as a food-grade propellant, medical-grade gas, and prescription drug. It's legal to own it, but, like other inhalants, it's prohibited by the FDA to purchase and sell for the purposes of getting high. Each state has its own laws against it, and most treat the illicit sale of nitrous as a misdemeanor, with penalties ranging from small fines to a few months in prison.In what was likely the most significant federal crackdown on the gas, defendants from Philadelphia and New Jersey were charged with unlawful distribution of nitrous to an undercover police officer in the parking lot outside a Dave Matthews Band show at Washington, D.C.'s Robert F. Kennedy Stadium in 2001. At an appeal hearing, a District Court judge ruled that the dealers' attempt to sell nitrous without a prescription was, in essence, a misbranding crime, in violation of the Food, Drug, and Cosmetic Act, and the defendants' cases were sent back down to lower courts.Some environmentalists complain that nitrous is a greenhouse gas. Some music fans say the hiss of the gas keeps them up at night. Still others kvetch that the tank lines clog up the campgrounds, and that dealers use random tents as hiding places. One fan says he was jolted from his sleep when a tank was slipped under his tent and slammed into his head. Another said she had her tires slashed after disobeying orders not to move her car."They have a total disregard for anyone's well-being but their own," says Rodriguez, the security executive. "They're only there for one reason: getting that money. And they get it whatever the cost.""Nitrous has not been much of an issue at the Gorge [Amphitheatre]," home of Sasquatch! and other summer concerts, reports Grant County, Wash., Undersheriff John Turley. "We did confiscate one large bottle of the gas three or four years ago...[but] have not experienced any violence due to the usage of nitrous.""Mad adrenaline, mad money, mad pussy," says a Philadelphia nitrous dealer named Beef, explaining why he got into the business. He's standing outside the Electric Factory, in the club-cluttered Northern Liberties section of the city, near the end of a Wilco show on a Saturday night. Beef is with five of his gang mates; together, they have three watermelon-size tanks stored in Nike gym bags, with reserves stowed inside the trunks of their cars. One of the dealers, an older man who looks to be in his 50s, sits in an illegally parked SUV—a hiding place for tanks in case cops come.A meter-reader approaches—a black woman, who notices the tanks. Immediately, a tall dealer named Jimmy, who wears a baggy gray sweatsuit and looks like Shaggy from Scooby-Doo, diverts her attention. "Damn, what's a fine-lookin' girl like you doing as a parking lady?" he asks, approaching her. She smiles, charmed, and leans against the wall next to him. "I just gave out my last ticket," she says, letting the gang off the hook. Later, Jimmy notices an Electric Factory security director pulling into the parking lot. Jimmy is asked whether the director ever puts the kibosh on the nitrous parties. "He works both sides of the fence," Jimmy explains. "Most of the time, he's cool, but just like women, he wakes up every once in a while with PMS." (At a later show, on a blisteringly hot day in Baltimore, Jimmy cooled down by emptying the contents of two nitrous balloons directly onto his face. Then he hoisted a clump of black balloons into the air and barked his sales pitch: "Once you go black, you never go back!")All of the nitrous dealers are civil, with the exception of the older man, who warns against taking photographs. Beef, a husky Italian-American from South Philly, has a tongue ring, a lazy layer of facial scruff, and a pair of young daughters at home. Twenty-four years old, Beef says he operates independently with a couple of associates, who together pocket about $50,000 a weekend in the summertime. He offers a handshake and a free balloon. It produces a pleasant sensation from head to toe.So where did the term Nitrous Mafia come from, anyway?"I think we use it as a negative connotation, like death tax instead of estate tax," offers Noah Wilderman, who has followed Phish since the early 1990s and is making a documentary about them. "It's definitely kids and bosses, but does that make it a mafia?" His most vivid memory of the gas dealers was when Trey Anastasio played with the Baltimore Symphony Orchestra, which attracted an upscale crowd. "I'll always remember a hundred people in ties and dress shirts passing out on the grass," he says."They say we're all city guys and not hippie guys," says Beef. "That's why they made the Mafia up. Because of guys like us, who don't blend in, wearing Jordan pants and $200 Jordan sneakers. These kids come out like bobos in their hippie T-shirts."Beef denies that nitrous leads to problems, and with a jovial, appealing demeanor, he seems anything but dangerous. He says he's smarter than most dealers. "Some people are ignorant and blast it all night," he says. "But I try to be respectful." Asked about the violence, he says, "Yeah, but you can get in fights over anything."A few fans admit that some of the dealers are cool—and that much of the violence isn't caused by them, but by stoners desperate for free gas. "These kids turn into hippie crackheads and hover over that fucking tank and have no money left," says Sean. "And they beg and beg, and the next thing you know, you got one hippie yelling at a bunch of mob kids, and that's when fistfights break out."Elliott Dunwoody, tour manager for the band Bassnectar, once observed one needy fan putting his lips directly to the nozzle of a tank: "He actually tried to sip up the bit of nitrous that gets released after they pull the balloon off," he says. "The kids beat him up."But other fans say that nitrous enhances the concert experience, and appreciate the gas mob. "I love the balloons," says Bobby Goodlife, a nightlife promoter from Baltimore. "They're just fun."When the Wilco show empties from the Electric Factory, the Philadelphia crew springs into action. Three of the men squat down like catchers, each straddling a tank between their thighs, and begin inflating balloons at a rapid clip. With a half-filled balloon dangling from his mouth and sweat dripping from his brow, Beef is particularly dexterous, able to hold five inflated balloons in his left hand, fill another in his right, and still manage to collect money from customers.The three other men serve as lookouts and runners. The older guy holds a clump of 10 purple balloons high in the air like a cotton-candy vendor. "Ice-cold fatties, right off the tank!" he yells to concertgoers, who have now flooded the sidewalk, eager for a slurp of the gas. A bald dealer named Carlo, clad in an '80s-style nylon Phillies jacket, sells five fatties to a man in a limousine rolling by. He offers another fan an entire tank—"wholesale," he says—for $200. Then he gives a free balloon to a legless, homeless man parked in a wheelchair nearby.A huffer named Stuart Woolf, who is resting against a chain-link fence, balloon in hand, is asked why he appreciates the gas business. "Because nitrous is the best orgasm I've ever had in my life," he says.There are signs that music fans are fighting back in larger numbers to keep the gas out of the scene. After the death at the Vibes, a vigilante group called the Wrecking Crew, born out of the Grateful Dead Family—fans who follow the band, year after year—retaliated by smashing up a truck with Pennsylvania tags and leading chants of "NO NITROUS!" to a chorus of festivalgoers. "The guy who owned the truck was dealing nitrous all weekend and had been followed back to his truck by the Family," says a fan.A video currently circulating on YouTube depicts two Wrecking Crew soldiers taunting the Nitrous Mafia while dancing around a stolen tank wrapped in a sign reading "100% $cum." "Hey, Nitrous Mafia motherfuckers! We stole your goddamned tank!" yells a man, face concealed by sunglasses and a towel, middle fingers raised. Midway through the clip, a soiled pair of women's panties is thrown at the canister.Security guards, too, say they've had enough, claiming they're tired of being accused of being in on the take. Inside a small Irish pub in Worcester, Mass., Rodriguez, the director of Marker Security, which has staffed the Vibes each year since the inaugural Bridgeport festival in 2000, tries to explain the difficulties of controlling the tank-toting dealers at an event as large the Vibes, which last year attracted 30,000 fans. "If two of my guards try to walk over and take their tank, they're not walking back," says Rodriguez, 36 years old, cupping a bottle of Bud Light between his oversize hands. His six-foot-two, 300-pound frame hulks over the table. "My guards aren't about to take their lives in their own hands and get beat up," he says. "Not for $8 an hour."The nitrous dealers have different strategies for dealing with security, says Sean. "At Vibes, we brought in 30 tanks and planned to lose about five to security," he says. "At All Good, different crews would take a turn throwing a tank at the fuckin' security. We'd hide the rest, and they'd drive away with one tank, all proud. Then they'd come back an hour later and we'd give 'em another one. Usually we'd give 'em a half-empty or almost-empty one. As long as you keep giving them a bust once in a while, it looked like the security was working. They thought they were hurting us a lot more than they were.""The cops have no idea how far most of these kids are willing to go," he adds.Musicians are also starting to speak out. "It's not something that needs to be a part of the music," says Christopher Robin, of the Christopher Robin Band. "Emotionally, I don't want to see it. There's nothing good about it. There are no success stories.""If someone wants to go hit a whippet in their hotel room, that's great," says Richards of Umphrey's McGee "But not to the point where it gets to be a very controlled monopoly on the tour. They're just simply out there to make as much money as they possibly can and leave in their wake the destruction—whether it's the garbage or the people they might have beaten up along the way."Rodriguez swears to me that this year's Vibes will be different. He has a message for the nitrous dealers: "Enough is enough. We're no longer going to sit here and have you ruin our festivals. We're gonna take it back. If you're going to come and try and ruin our scene, we're going to shut you down."But, minutes later, he pauses, thinking about his decade-long history fighting the balloon men. "I don't think we'll ever wipe it out," he concedes. "It's inevitable. We can only hope to control it."This story was produced by SW's New York City sister paper, The Village Voice.