It was past Halloween's witching hour when Yelle took the stage, and the energy of San Francisco's Mezzanine was about to hit the roof and course through the bedecked revelers. Tired feet and achy joints watched impatiently as the large YELLE banner was set over the DJ table and each small pumpkin was lit to spell out Y-E-L-L-E. Sheets strung across the room displayed zombie and skeleton graphics, glittery red flames adorned the walls and anxious partygoers leaned against a spooky leafless tree in the center of the room. Then all of a sudden it was go-time, the crowd surging forward as soon as the group stepped into "Tristesse/Joie."

Singer Yelle (Julie Budet), DJ Tepr and drummer GrandMarnier came onstage in black and white diagonal stripes, somewhat understated for the usual bright colors and PVC sheen. Yelle herself wore her stripes from fingers to toes, her black mini dress accented by a red fringe collar strung with mini faux skulls-a Halloween chic.

Despite the openers that sweated through their sets, Yelle commanded the stage effortlessly in her outfit. A French artist playing to a widely English-only audience, Yelle tried to mount the language barrier through the physicality of her performance. She staccatoed her movements, marched through her lyrics, cocked her hips and punctuated her words with pointed finger. She flung herself into her songs, punching the air to Tepr's beats.

The crowd went into a frenzy as soon as Yelle hit the stage, and the poor souls who staked out spots in the front were squished, pushed and stepped on as the crowd rushed to get closer to the brightly lit stage. Three hours of drinking in anticipation for the main act erupted into madness. A Golden Gate costume lost its suspensions ropes in the pulse of the masses, but the crowd didn't see true craziness until the group broke into their breakthrough hit "Je Veux Te Voir."

For the most part, they played straight into their songs after a quick "thank you" or "merci beaucoup," but occasionally the guys of the group would speak in stilting English. "Excuse me," one said. "Do you know how to scream?" The crowd responded enthusiastically, perhaps even without blinking to possibly the most polite and formal request ever to rock out. Or perhaps it was a rude insinuation-either way, fans were too jazzed to notice.

Yelle covered Pop Up entirely, even the songs not normally suited to an electro-poppy environment. Yelle introduced "Les Femmes" as a song about a girl liking another girl, and in a nightclub that chanted "No on 8" in between acts, the song took on another personality. Normally a low-key and slower number, the group pumped up the song with Tepr's new spin on its melody.

After their finale, a stream of beleaguered partiers started to leave the joint while others, still intoxicated and high on the performance, clapped and cheered for Yelle's return. The group ran back onstage quickly, trying to catch the party-poopers mid-exit.

Their encore was triumphant, and they played two more songs. The singer disappeared momentarily, and the guys were left to keep up the beat (and to keep fans from thinking the show was over). With a heavy French accent, one asked the crowd: "Do you know how to headbang?" Yelle then emerged, a foot taller with a platinum blonde wig, seemingly engendered by both Tina Turner and a pastiche of '80s hair bands. Coupled with solid, heavy drums from GrandMarnier, Yelle returned to "Je Veux," this time the nightclub singing along to the raunchy chorus.