Caitlyn Jenner Makes Surprise Appearance at Boy George Concert at L.A's Greek Theatre: Details and Pics

"Caitlyn Jenner in the house for her first Boy George concert!" she told the cheering crowd

Boy George's Culture Club band had two surprise guests at the group's concert in Los Angeles on Friday night—and one of them was Caitlyn Jenner!

The 65-year-old Olympian and star of the new E! docu-series I Am Cait, which premieres on Sunday, was greeted a standing ovation as she took the stage at the Greek Theatre to introduce the New Wave pop group, which rose to fame in the '80s with hits such as "Do You Really Want to Hurt Me?" and "Karma Chameleon."

"Caitlyn Jenner in the house for her first Boy George concert!" she announced, as seen in a video posted by Entertainment Tonight. "This is going to be a good group. Thank you so much. Enough about me. Thank you for being here tonight. Um, this is so much fun for me and let's hear it here at the Greek Theatre for Boy George! Let's get it going!"

"I expected a standing ovation for her and I wasn't disappointed," Boy George told the crowd after thanking Jenner for her intro, according to ET. "We need to celebrate the kinds of changes that are happening."

Jack Black, 45, was the other surprise guest. The actor and member of the rock band Tenacious D joined Boy George, 54, onstage to perform David Bowie's 1972 song "Starman."

Caitlyn wore a black leather biker jacket over a beige form-fitting above-the-knee dress with a pencil skirt and black leather high heel boots, marking her second "rocker chic" look in a week.

She has showcased a number of trendy styles since she began her transition to become a woman. Caitlyn, previously known as Bruce Jenner, revealed her female name and appeared in women's clothes for the first time on the cover of Vanity Fair on June 1.

Caitlyn attended the Culture Club concert with BFF Candis Cayne and the two were seen dancing together in the audience.

Caitlyn also got to go backstage before the show. Musical director and songwriter John Themis shared a selfie of the two.

Caitlyn Jenner pre gig at the Greek Theatre

Posted by John Themis on Saturday, July 25, 2015

Watch Caitlyn Jenner's new docu-series I Am Cait when it premieres this Sunday at 8 p.m. on E!