Kristin, a shy, blonde 14-year-old with braces who hugs herself nervously while talking, began drinking and smoking marijuana at age 12, but neither drug had the pull of ecstasy, which she first tried in the spring of 1999. "I didn't think it was gonna be that good, but once I tried it, it was like my life," she says. "I couldn't wait until the next time I did it, so I did it the next day."

Like the club kids who proselytized about ecstasy ("Everything begins with an E" was a raver mantra), Kristin found herself E-vangelizing about the drug the way Timothy Leary's followers extolled the virtues of LSD. "Once you do the first pill, your whole perspective on life changes," she says. "Your whole view on the world around you, the way you look at people. I would look at clean people and be like, 'What is wrong with them? They don't even know what they're missing.' And I wanted to show people ecstasy."

Though ecstasy is relatively expensive for cash-poor teenagers, Kristin says she rarely had to pay for it. "Most girls I know who don't pay for their drugs had sex with the dealer and he'd give it to them for free, but it wasn't like that for me," she says. She got the drug by hosting afternoon ecstasy parties at her parents' home.

On the drug, "if someone says something just a little nice, like 'Hi, how are you?,' you'll be like, 'Oh, my God, that's so nice of you,' and you'll fall in love with them on the spot," she says. But the bonds created by the drug vanish just as quickly. "I remember this kid who I was so in love with when I was on ecstasy," she continues. "Then the next day I called him and told him to come over and he said no, and I was like, 'Whatever, I don't really care about you anyway.' He wasn't important to me at all -- we just had that connection when we did E together. I call it 'E love,' 'cause that's what it is, really."

After she began to miss more school, her mother read her diary and "saw a completely different person 'cause every page was filled with 'Oh, my God, I can't wait till the next time I can do E,' " she says. She's been enrolled with Daytop since the fall, but it's still difficult for her to imagine life without ecstasy. "I give myself pats on the shoulder every day, like, 'Today I'm clean another day,' " she says, "but it's still constantly in the back of my head, because nothing can make me feel like that."

"E was around every weekend," says Charlie, 16. "My brother played on a soccer team with my dealer, so I knew him well."

In the early nineties, when ecstasy was prevalent only in European rave culture and the few underground American clubs that identified with it, two outer-borough teens named Frankie Bones and Michael Caruso went to England to check out London nightlife. They were fateful trips: Bones was inspired to begin throwing raves in Brooklyn, and Caruso started Manhattan's first techno party at the Limelight. Eventually, Bones's "Storm Raves" planted the seed for the U.S. rave scene; the drug-distribution network Caruso allegedly ran at the Limelight gave the city its first bona fide ecstasy bust.

"We weren't really even aware of ecstasy until the Limelight case in 1995," says Brennan. Indeed, the DEA-NYPD joint investigation into the Limelight began only after police were contacted by the parents of an 18-year-old New Jersey man who had died from an overdose of ecstasy he had allegedly bought there. Until 1997, ecstasy wasn't even a controlled substance in New York State.

By then, the drug was already old news in clubland -- it had started spreading to the mainstream. "Law enforcement is always playing catch-up," Brennan admits. Because it got such a late start monitoring the ecstasy trade, Brennan says, the NYPD's lab doesn't "have a baseline to start with in terms of assessing the purity of ecstasy pills" the way it does with cocaine or heroin. Lately, however, Brennan has been surprised to find supposed ecstasy pills that actually contain antihistamine laced with insecticide. "We're seeing all kinds of adulterated substances," she says. "You honestly don't know what you're putting in your mouth when you're taking ecstasy."

The current ecstasy explosion has made the market for fakes even hotter. "People don't have qualms about what they sell as ecstasy," according to Murray, "as long as people pay for it." Indeed, when the NYPD used the nuisance-abatement law to shut down the Tunnel last year after a raid targeting ecstasy dealers there, only four of the pills that were seized tested positive for MDMA. (Tunnel has since reopened.) And as user demand builds for "brands" like Mitsubishi -- a particularly potent pill illicitly stamped with the car manufacturer's three-diamond logo -- drugmakers are putting the same insignia on impure pills, much the way knockoff-makers sew Prada labels onto cheap backpacks.

But adulterated or weakened pills are the least of law enforcement's problems: Smugglers are getting more sophisticated, and other organized-crime rings are competing with the Israelis. Several men have been nabbed at JFK wearing skintight bodysuits that held more than 7,000 ecstasy pills each; Customs officials have also found pills hidden in software packaging, stuffed animals, and secret compartments in carry-on luggage. In March, Customs scored its first internal seizure when it arrested a passenger flying into JFK from Amsterdam who had swallowed 2,800 pills in 70 condoms.

At the same time, "organized-crime groups are putting their feelers out" to the ecstasy trade, according to Murray. "There's so much money to be made that these groups are saying, 'Let's get this going on,' " Murray says. "We're going to see a stronger Mexican connection, a much stronger Dominican connection. We're going to see bikers who were running methamphetamine labs in the Midwest convert those labs into ecstasy labs. We've already seen it in Vancouver. The only difference is you start with a different chemical."