SAN FRANCISCO -- Nobody really saw electronica twins the Crystal Method perform at San Francisco's Warfield Theatre on Thursday night. But it wasn't because the venue was empty.

In fact, it was a sold-out show. And the Crystal Method even turned up and played right at the center of the stage.

It's just that nobody could make them out through clouds of smoke and banks of strobe lights.

The theater was packed with club kids and hipsters, all of whom danced enthusiastically to the tunes spun by opening DJ David Holmes, endured a set by up-and-coming electronica duo Propellerheads and let their dancin' feet and bobbin' heads go buck-wild when DJ Fatboy Slim took his turn behind the wheels of steel.

When the fog machine kicked into overdrive midway through Fatboy Slim's set, however, it was clear that the headlining L.A.-based Crystal Method would be enveloped in the same haze. But when the dynamic duo took to the stage accompanied by a blinding barrage of lights, their message shone through as clearly as their sound.

The duo had but one thing to say: Just close your eyes and feel the music.

Those who dared to watch Ken Jordan and Scott Kirkland had the chance to see nothing more than two shadow figures playing, punching and tilting a group of keyboards and samplers.

When the beats came fast and furiously, they were unstoppable. When the more ambient bridges filled the venue, you could see a majority of folks with their eyes shut tight, taking in the energy and protecting themselves from the blinding stage lights.

Dressed in their trademark designer suits, Jordan and Kirkland put on a show that was as sharp as their couture. Songs such as "Busy Child" and "Vapor Trail" (RealAudio excerpt) had the girls in tank tops and boys in baggy pants tripping out, from the dance floor in front of the stage to the final rows of the balcony. Those who chose to remain in their seats couldn't help but nod their heads to such songs as "Keep Hope Alive" (RealAudio excerpt) and "Trip Like I Do," drinking in the complexity of the material.

The Crystal Method's overwhelming sound-and-light show demanded it.

Earlier in the evening, opening act the Propellerheads performed a curious and occasionally engaging show that mixed live instrumentation on bass and drums with loops, samples, drum machines, scratching and human beat-boxing. An intriguing mix? Unfortunately, no. Live instrumentation gives artists -- even those from the world of electronica -- the chance to expand their recorded work and perhaps to play around with the arrangements a bit.

Drummer/DJ Will White and bassist/keyboardist/DJ Alex Gifford failed to do this when they took turns playing live. They seemed to be reproducing exactly what was on their DAT, and their show suffered for it.

It might have been interesting if they had chosen to play some of their more complicated beats and basslines, but they didn't. Adding insult to injury, they didn't even offer up their current hit, "History Repeating." To the Propellerheads' credit, however, those who were dancing never stopped.

Fatboy Slim (a.k.a. former Housemartins bassist Norman Cook) followed the Propellerheads, but only the most die-hard of fans would have been able to tell that it was him at first. Perched in a DJ booth high above the dance floor and way off to the left where no one in the lower-level seats could see him, Fatboy Slim took to the decks with no announcement and spun a happy mix of hip-hop beats, up-tempo basslines and well-placed samples.

Spinning with an ear-to-ear grin, he played such danceable tracks as Better Living Through Chemistry's "Going Out of My Head" and his excellent dance remix of Cornershop's "Brimful of Asha." ( Memo to Warner Bros.: The crowd response to this remix was huge, so release it in the U.S. already!)

An excellent between-set DJ, Fatboy Slim constantly looked out of his perch to see if he was keeping the booties wiggling. And he continually alternated the pace of his beats from rave-fast to funk-slow at intervals that only the best groove-meisters know how to find.

Which brings us back to the Crystal Method. They, too, demonstrated themselves to be knowledgeable groove-smiths. But damned if you could see how they were doing it.

The smoky haze was a neat trick. And it worked.