They also unmasked the couple accused of running it: Robert Chambers, 41, the “Preppy Killer” who strangled a young woman to death in 1986 and served a 15-year sentence for it, and Shawn Kovell, 39, his longtime companion. Chambers, handsome and arrogant, became a tabloid staple in the 1980s for his crime; despite being a product of Upper East Side privilege, he’d fallen into a life of indulgence and depravity. And although he’s had numerous opportunities to right himself in the years since, he always returned to a path of drugs and destructive behavior. Now, Chambers faces drug-selling charges that could return him to jail for the rest of his life. (Kovell, too, faces drug charges, but has no prior record.) “I do believe he’s a sociopath,” says Linda Fairstein, who prosecuted him for killing the girl. “He had absolutely no remorse for any of the things he’d done in his life.”

Chambers appeared troubled from an early age. By the time he was 14, he was using alcohol, marijuana and cocaine, says Fairstein. Repeated stays at detox facilities were fruitless. Chambers also had a penchant for stealing, she says; he lifted a teacher’s wallet, resulting in his expulsion, and pilfered a friend’s credit card, to which he charged $3,000 in a single day.

Then, one night in 1986, he ran into a friend, 18-year-old Jennifer Levin, at a trendy bar on the Upper East Side. The two left together and headed to Central Park, where Levin’s body was found the next day, battered and nearly naked. Chambers later told police he accidentally strangled her during “rough sex.” He seemed all the more chilling after he later appeared in a video in which he twisted the head off a doll—“Oops, I think I killed her,” he said. Also on the tape: Kovell, who met Chambers after Levin’s death and fell in love with him. Though the case went to trial, Chambers pleaded guilty to manslaughter while the jury was still deliberating and received a five- to 15-year sentence. He ended up serving the maximum because of 27 alleged infractions while he was locked up, including nine for drugs. Fairstein, who saw records of Chambers’s infractions in jail, says that at least one time, Chambers was caught with drugs immediately after Kovell’s visit. (It’s unclear how, or whether, Kovell slipped Chambers drugs. But women often sneak drugs to men in prison by hiding them in condoms in their mouths, says Fairstein, then pass them over during a kiss.)

When he was released in 2003, Chambers reunited with Kovell. They traveled to Ireland and got married, says Kovell’s godmother, Connie Hambright. Then they moved to Dalton, Ga., to stay with her. Though they tried to keep a low profile, the local paper eventually discovered Chambers. “I am sorry if my being here is a cause of concern,” he told a reporter. “I’m just trying to … move on.” Hambright says Chambers quickly won her over—helping her nephew build his house and rising early to work at a dye factory. “He’s not the monster they portray him as,” she says.

After seven months in Dalton, Chambers and Kovell returned to New York. Kovell’s mother had died, leaving her the co-op. It seems it didn’t take long for the two to revive a drug habit. Msgr. Thomas Leonard, a priest who tried to help Chambers in the past, reached out to him, but Chambers had already succumbed. “He couldn’t lick the problem,” says Leonard. The next year, Chambers was stopped in Harlem on a traffic violation; police found traces of heroin in the car and a judge ordered him to jail for 100 days.

He managed to stay out—until now. After the tip-off from neighbors, police launched an undercover investigation of Chambers and Kovell. In drug buys caught on tape, investigators bought baggies in and near the couple’s apartment. It was an “open and notorious” business, says D.A. Robert Morgenthau. (Prosecutors say that, during their investigation, Chambers “expressed involvement in financial-related crimes,” but have declined to elaborate.) It doesn’t help Chambers’s standing that he scuffled with the officers who raided his apartment. At the couple’s arraignment last Thursday, each pleaded not guilty. Chambers looked haunted; Kovell appeared strung out, her foot shaking. “They’ve been together 15 to 20 years,” Kovell’s attorney said afterward. “Whether it’s love, co- dependence, I don’t know.” Whatever it is, it’s apparently all they had left.