In a dingy pocket of the city, up a dismal fluorescent-lit stairwell, is the Jon Sims Center for the Arts. Last Saturday the eerie quiet of the linoleum steps belied the veritable revival going on upstairs, where the crowd stood and swayed with the urgency of people who just couldn't stand to sit down anymore. And up front, lifting them up and egging them on, was Gwen Avery.

"We're gonna give this one up to God," Avery said, before launching into a funked-up rendition of the gospel classic "Precious Lord."

As she strutted about the stage like a chubbier James Brown, Avery made eyes at the audience with a half-crazed, half-flirtatious edge. When Avery commanded her guitarist to "break it down," a woman in the front row held her hands to the heavens in true revival style. Moments later Avery tumbled to the ground and splayed her legs in the same direction, letting go with a series of shrieks.

The scene was startling in the unassuming space of Jon Sims, which, with its white, exposed brick walls and folding chairs, could easily come off as cold. But the packed house pulsed with warmth – and that was before the music started, while Avery, clad all in black from her fedora to her unbuttoned pants, stood on the fire escape smoking.

It's remarkable that even 100 people knew Gwen Avery's work well enough to show up. She didn't release a CD until just over a year ago, but it was clear from her energetic performance that her many years onstage have taught her a few things. She doesn't break new ground, playing instead an assortment of standard blues, gospel, and R&B, and even her original compositions sound like typical fare. Sometimes her voice leaps out at you, but other times it's overshadowed by the energy she exudes.

It wasn't just Avery who moved the crowd. She had a band backing her up, dubbed the Sistahs, whom she compared to the Blues Brothers. "They tryin' to be blue, but we really blue." There was a drummer in a sequined vest and cargo pants and a bassist wearing a porkpie hat and a nose ring. Then there was guitarist Alberta Jackson, her hair in cornrows, who looked like a banker (turns out she's a tax accountant) and played like B.B. King.

During the set, which included Avery's original anthem "Sugar Mama 2K," Leonard Cohen's "Suzanne," and Nina Simone's "Sugar in My Bowl," the audience quickly learned that Avery wasn't going to tolerate much sitting. Raised largely in the confines of her grandmother's juke joint in Pennsylvania, Avery didn't waste much time on niceties. "We encourage you, of course, to dance," she told the crowd. "Politely, get off your ass."

If the crowd seemed a bit sluggish, Avery would bound into the audience, at one point taking a woman in an embroidered sweatshirt into her arms for a twirl across the floor. Even the guy from the food table, who looked like he might have bought himself a few cups of wine, got up and danced, as did the sound technician, who had to run back occasionally to adjust the board.