Unfortunately for the madams, the FBI learned about the Circuit, too. Working off a tip from one of Maier’s clients, the Feds gradually pieced together the workings of the network. In two waves of indictments–in New Orleans in April and in Miami three weeks ago–prosecutors moved against Maier and two dozen co-defendants in 13 cities, including New York and Chicago. Maier and her mother, who was also indicted, pleaded guilty to conspiracy charges in May and will be sentenced in December. But according to Maier and another mad-am who was part of the Circuit, the Feds have busted only part of the ring. More than 50 years old, the Circuit may involve over 100 brothels–many of which might still be in business.

Prosecutors marveled at the entrepreneurial savvy of the madams. “These were not dumb girls,” said Richard Gregorie, assistant U.S. attorney in Miami. What distinguished the Circuit from run-of-the-mill brothels–and made it ingenious–was the way prostitutes jetted around the country, staying in no one city for more than a few weeks. Since the “girls” moved on so quickly, the madams didn’t have to worry that they’d take the best clients and set up competing businesses of their own. The men, Maier says, “loved the variety,” descending hungrily on the brothels and sometimes unloading thousands of dollars in one night.

It was a lucrative arrangement. Prostitutes would typically rent a room for a week–paying $350, for instance, at Maier’s cozy Victorian house in New Orleans. The madam would then book a cavalcade of clients at rates usually ranging from $300 to $400 an hour. (Maier’s mother reported one prostitute’s schedule on a wiretapped call: “She saw David, Gordon, Dan. She is seeing Allen now… She’s going to see Kenny at 3:30, Victor at 4:30 and Larry at 5:30.”) Hooker and madam would split the proceeds 50-50. A prostitute could earn $5,000 in a typical week at Maier’s house. The madams, who had as many as six rooms per brothel, could earn several times that. And since they were ex-prostitutes themselves and knew the johns well, “the girls felt safe,” says Paula Cherish, 38, a Pittsburgh madam who has also been indicted and pleaded not guilty.

Not that the Circuit always functioned smoothly. The madams “had their catty moments,” says Cherish, who’s working on a book, “Modern Day Madam,” about the Circuit. Cliques formed; there was backbiting. Madams felt threatened by Circuit peers–some in the same city–who seemed too greedy. In one wiretapped call between Cherish and Maier, the two gripe that Anna Yeung, an indicted madam in New York who has pleaded not guilty, “is trying to steal everyone’s girls.” (Yeung’s lawyer did not return calls for comment.) The prostitutes could also prove troublesome. One absolute taboo: to encroach on a madam’s business by giving a john your personal number. Cherish fined one girl $500 for that sin, according to wiretaps.

Those petty disputes are a far cry from the current travails confronting the Circuit madams. Maier–who stresses that she “takes full responsibility” for her situation–and her mother are bracing for prison. Their co-defendants are either talking to prosecutors or gearing for trial. Whether their convictions will succeed in wiping out the Circuit remains to be seen. “They got a couple of top houses,” says a doubting Maier. But “the Circuit is always going to be there.”