What do you do when you're on a break from working with the most innovative band in the world, a band that knocked the music industry on its backside with a pay-what-you want release and then went on to top the charts the traditional way? If you're Thom Yorke [ tickets ] and that band is Radiohead [ tickets ], you assemble a little side project and continue to blow minds by playing by your own rules.

That's exactly what Yorke and company did on Monday (10/5) at the Orpheum Theatre in downtown Los Angeles, his second night at the ornate and intimate venue after a surprise warm-up show Friday (10/2) at the Echoplex. All three were announced just days before they were held and sold out in short order.

That sort of fan devotion would put a lot of pressure on an unproven act, but Yorke and his combo--so new the marquee at the Orpheum simply read, "Bill Silva Presents ??????"--were unfazed. It probably helped that his new collaborators were no slouches themselves. The band featured Flea on loan from the Red Hot Chili Peppers on bass, noted Radiohead/Paul McCartney producer Nigel Godrich on keyboards, guitars and backing vocals, former Beck/R.E.M. sideman Joey Waronker on drums, and Brazilian percussionist/David Byrne sideman Mauro Refosco.

"In the past couple of weeks I've been getting a band together for fun to play 'The Eraser' stuff live and the new songs etc, to see if it could work!," Yorke wrote on Radiohead's Dead Air Space website. Never mind the fact that "The Eraser," Yorke's first and only solo album, was released in 2006 and is probably only familiar to the most devoted Radiohead fans. That Yorke and his collaborators managed to hold the sold-out crowd rapt and standing for nearly all of the 85-minute set, playing unfamiliar material, speaks volumes of his charisma and the relentless groove-mongering of his bandmates.

Freed from the party-rock schtick of the Peppers, Flea managed to keep his clothes on and show he's a serious, accomplished musician, laying down monster bass lines matched by his violent head bobs and body thrusts. Yorke sang in his trademark clarion-call voice, occasionally opting for a falsetto so moving it sounded like a wounded animal. When not occupied with upright piano or guitar, he offered his usual spastic interpretative dancing. While Yorke and Flea were the visual and emotional thrust, the rhythmic attack came from the back-riser trio of Godrich, Waronker and Refosco, who churned out Afro-electro beats so infectious they could move a dead man.

While Radiohead has a catalog of classics it can churn out live, Yorke and his new bandmates simply relied a mix of hypnotic, trance-like rhythms, delivered with the utmost intensity. With Yorke's stamp, the new combo of course sounded reminiscent of Radiohead at times, but also recalled such post-punk powerhouses as Gang of Four--particularly when Flea traded in his bass for a recorder--as well as the Talking Heads and David Byrne's collaborations with Brian Eno.

Highlights included "Black Swan," "And It Rained All Night" and "Atoms For Peace" from "The Eraser," as well as "The Hollow Earth," the B-side from Yorke's just released new vinyl-only (for now) single, which, with its skittering beats, sounded like a lost "Kid A" track. Yorke also unveiled three brand new tracks that he performed solo, including falsetto-heavy "Lotus Flower," which he said he'd been working on during "his holiday." As the show wound down, Yorke admitted it is was a bit of "a downer" because this impromptu stint had come to and end, but then vowed that he and his new bandmates will do it again. Catch them when you can.