Then, in the mid-nineties, "a friend asked, 'Have you tried smoking crystal?' " After his first hit, John knew he had found his new drug. "I thought, This is fabulous. I want to do this all the time. There was a subtle, warm euphoria, a strong feeling of eros. I knew that I would have to work very hard to not become a drug degenerate." He laughs. "That didn't last very long."

John kept his crystal use in check for a few months, but after his boyfriend moved out in 1997, he became unhinged. "During the summer of '97," he recalls, "I smoked crystal — and had sex — on every square inch of Fire Island." One particularly memorable bender lasted from Gay Pride Weekend, in late June, to July 4. "I basically went ten days without sleep."

John confessed his problem to his therapist, who suggested that he go to an AA meeting. But he noticed that there were crucial differences between the addictions. "Alcoholics are often introverted types," John says. "But with crystal, you're out all the time, you never miss a day of work. You're like Superman." (Also, as he points out, "most alcoholics wouldn't know what it's like to masturbate for three days straight.") In July of 1999, a local CMA chapter was started. "I'll never forget the first meeting," he says with a laugh. "It was just me, a transsexual, and another guy." It's a growing fraternity: Now there are more CMA groups at the Gay Men's Health Crisis than any other twelve-step program.

Crystal is having a devastating effect on gay men not only in New York but in other big cities. "Look at the syphilis rates in Seattle," Klitzman says. "They've skyrocketed along with crystal's popularity. People's judgment is decreased on this drug, which leads to wildly unsafe sex, which can in turn drastically increase the risk of HIV infection."

"We're seeing a strong correlation between crystal and HIV infection," agrees McCabe of the Pride Institute in New York. "People who have weathered years of staying safe are getting into crystal and then testing positive."

The crystal-sex connection becomes clear at the CMA meeting, when the moderator warns the group not to be too explicit in relating stories of "crystal-triggered" sex; such tales could easily cause a relapse. Moments later, one man cuts short a story about a threesome. And if recovery from most drugs is measured in days and months, time away from crystal seems to be clocked in minutes and hours. A handsome, well-dressed guy begins by mentioning that he's not a New Yorker at all; he's here on business. He'd promised himself that he wouldn't use while here, but gave in over the weekend. Another admits that just this morning, on his way to work, he ran into an ex-drug buddy and before he knew it, he blurted to his friend: "I wanna get high."

"I have to never, ever run out of this." those were best-selling author David Sedaris's thoughts when he took his first bump of crystal way back in 1980. To Sedaris, who was working as a waiter in North Carolina, the drug's appeal was simple. "With ecstasy and cocaine, you're always chasing that first high," Sedaris explains. "But with crystal, you find it every time."

Sedaris quickly became friends with his dealer's customers — they even formed a crystal collective of sorts. "We used the word manifesto a lot," Sedaris says, "and we were into creating these bizarre abstract art projects." Typically, Sedaris offers a counterintuitive take on crystal as aphrodisiac: "I've heard about guys staying up for two days and having sex, but that would never happen with me. I'd be trying to hustle the guy out the door so I could paint envelopes."

But the drug soon consumed Sedaris. "I once told a friend that I left my keys on her kitchen table, just so I could get in there and steal her drugs," he admits. And colored envelopes aside, it took a heavy toll on his creative life. "I look at the stuff I wrote then and it's just complete trash. Nothing would have happened during the course of the day, but somehow everything meant something."

His withdrawal was also unexpectedly painful: "I couldn't get out of bed, and when I wasn't in bed, I was curled up in a ball on the floor crying. It was like Lady Sings the Blues! I remember thinking, Oh my God, I am a drug addict. I thought I was an artist, but I really was a drug addict."

Still, Sedaris says that crystal's lure remains potent. "There are times when I think, God, if I had some crystal right now, I could get so much done," he says. "And if there was a drug that combined coffee and crystal, I'd be finished!" Sedaris pauses. "But all I have to do is look at my writing back then," he says. "And I'll think: Nah."

Precisely why crystal — whose side effects range from heart attacks to psychosis — is so tough to kick is a question that stymies public-health officials, even though it is chemically similar to prescribed drugs such as Desoxyn and Ritalin. "What we do know, however, is that the drug is highly addictive," says Klitzman. "The brain develops a desperate need for this substance, which makes the road to recovery long, very painful, and filled with relapses."

Recovering addict J.L. is in the midst of that struggle: After a disastrous three-year affair with crystal that included a bitter split from his partner and testing positive for HIV, he fled New York for a rehab clinic in Minnesota. An actor and voice coach, J.L. says that being away from the city he loves has been tough — his first relapse came when he read a story in the New York Times about a play his ex-boyfriend had worked on coming to Broadway. "That blew my mind," J.L. says. "He was going to Broadway, and I was in rehab. I immediately went out and used."

J.L. is clean now, but worries that gay life provides daunting challenges to sobriety. "How do I stay sober and meet gay men? How do I exist as a social gay man and not come into contact with drugs?" He laughs. "And this is Minneapolis!"

Like many of his fellow New Yorkers who've moved to midwestern rehab centers, J.L. sees little but danger in returning to the city. "Some of the guys say they'll never come back to New York, and I'm not sure I can either," J.L. says. "You have to understand: Once you're in the loop in New York, there's a place to go and party every night." He pauses for a moment. "Nothing can compare to crystal, it just keeps you up there," he says in a voice that sounds both awestruck and sad. "Life only gives you that in moments."