You know what (most) actors are good at? Acting. Just like (most) singers are good at singing, and the majority of rock writers are mostly good at figuring out how to get a better credential than the one they have so they can use the “good” bathrooms (i.e. the air-conditioned ones in the artist area) and score something decent to eat besides waxy pizza and crusty midway gyros.

Which brings us to Oscar-nominated actress Juliette Lewis. In the fine thespian tradition of Jared “My So Called 30 Seconds” Leto and Billy Bob Thornton, Lewis has decided to give acting a break and concentrate on the rock. She seems to love it, and the couple hundred early arrivers at Lollapalooza lapped it up when Juliette and Licks ran onto the stage for their 11:30 a.m. set.

Wearing an Indian headdress like the one you had as a kid with two colorful plumes, skintight vinyl pants and a mesh tank over some complicated-looking bikini, Lewis rocked the stage like she was playing a dingy rock club at midnight, not a side stage in broad daylight. She had all the moves down pat: the Mick Jagger bounce, the spin where you raise your arms in rock triumph, the thing where you point at the guitarist and lean back into him and, most importantly, the move where you plant your foot on the monitor deliver a crazy-eyed stare. (She even did some crowd surfing; check it out.)

What she didn’t really have was much beyond a secondhand Stooges punk sound filtered through Sunset Strip glam metal moves. (Why settle for less when Iggy himself is playing later today?) As Chris already mentioned, it’s hot here today. Not really hot so much as bathed in the flame-throwing corona of the devil’s fiery shadow. My sweat is sweating. So, unlike Robert De Niro in “Cape Fear,” the one place I know I don’t want to be today is on the inside of those vinyl pants Lewis is poured into.

Though it was good for a laugh, the disco metal cover of Donna Summer’s boogie anthem “Hot Stuff” only served to remind everyone that at some point they would be visiting the med tent to get their blood replaced with chilled antifreeze.

Read more about Juliette & the Licks and all of Sunday’s performances on MTVNews.com …