In truth, NBS is less wild and crazy than it might sound on the airwaves. The musical revue, conceived by Robert Schrock with material from multiple songwriters, has always been more cabaret than Chippendales. The numbers range from comedy to earnest ballads, but not much of the content is sexy or overtly gay. Perhaps that's what made it such a draw for a girls' night out. But for some of the crowd, even the innocent nudity was almost too much.

"People get squeamish to see a naked body. Literally, grown women put their programs up to their faces when we open the show with 'Gratuitous Nudity,'" says longtime cast member John Cardone. That's the opening number that bucks burlesque's slow reveal—all eight guys start the show in the altogether, with a song that tells you exactly what you're going to see. The up-front undress helps audiences get over themselves.

Cardone has been with the show since its first anniversary, but the longevity prize goes to Scott Thomas, who opened the show in 2001 as his first job after college and has stayed for the entire run. "When the show started, it was only supposed to be, I think, like a six-week run. I wasn't expecting four and a half years," Thomas says with a laugh. "But you know, it pays the rent."

Musical director and accompanist Robert Ollis counts 30 performers who have filled the eight slots over the years, from long-timers like Thomas and Cardone to some who've done only three weeks. "A couple of other guys auditioned, were cast, and then lost their nerve before actually learning the show," he says.

Fabled NBS lore includes the story of a straight actor who got vetoed by his girlfriend. "He rehearsed with the cast, and then his girlfriend came to see a performance he wasn't in—he was going to go in the next night," Zak recalls. "He called the next morning and said, 'I can't go on tonight.'"

If the girlfriend envisioned anything untoward going on backstage, she needn't have worried. "It's [like] going to work. We just take off our clothes and go to work," Cardone says. "There was one guy who was a little inappropriate, but I think he was just nervous. He was new, he didn't know how to handle all of that, but then he figured it out very early. We don't really slap each other's ass; we don't talk about our genitals. We just do our jobs."

The obvious question, with group sales still coming in, is why close now? Zak says the company is simply ready for something new. "Everybody's a little tired, and change is always good. We feel like we're at one of these ebbs between the bachelorette season in the fall and the bachelorette season in the spring, and it's just time to move on," he says. "You just sort of know when to fold 'em."

At least they won't have to fold many costumes.

Naked Boys sings for two more weeks at the Bailiwick.