Lady Gaga Joins Semi Precious Weapons At London Club Gig

The Mother Monster pounds on the band's drum kit, stage dives during her surprise appearance.

Lady Gaga and the Semi Precious Weapons are besties, so when the glammy rock band had a club gig at the O2 Academy2 Islington in London on Wednesday night, guess who jumped on stage with singer Justin Tranter and the guys? Yep, the Mother Monster herself.

Gaga appeared in a bra and underwear, her hair done up in a beehive, wearing lots of eyeliner. Gaga is in London for two Monster Ball tour stops the O2 Arena, where the Semi Precious Weapons are opening for her. According to

target="_blank">The Sun, many of the women in attendance at the SPW show stripped down to their undergarments in honor of the pop superstar.

Gaga and the crew hit the stage with the SPW guys over the course of two songs, during which time she played drums, sharing the kit with the band's Dan Crean. According to gossip site Oh No They Didn't, the singer took a stage dive at the end of her impromptu appearance. In a video posted on YouTube, Gaga is heard whispering "Semi Precious Weapons" into the mic before the crowd begins chanting the band's name as well.

"We were so broke that we couldn't afford the f---ing subway, but what could we afford? We could afford two things: We could afford to be beautiful and we could afford rock and roll," Tranter is heard telling the excited crowd, with Gaga still at the drums. "On drums we have two of my oldest friends in the world, Daniel f---ing Crean and my sister, my soulmate, Lady f---ing Gaga!" He then tells everyone in the room, "I, I, I f---ing love you."

As Gaga exits the stage, Tranter shouts at her, "I love you, bitch."

The guys took to their Twitter later that night to share their excitement over the gig. "Tonight happened!! I love our London fans, and @breedlovenyc @ladystarlightny @ladygaga ! Magic!" the band wrote. "Panties and Booze. Thank you London. Lying in bed in London w/ an assortment of new friends. Tonight was Dirty Showbiz heaven. Thank u all. 2011 will be even more..."

Semi Precious Weapon's pal, artist Breedlove, tweeted a similar reaction to the night's events, writing, "Wow. London. Dirty Showbiz. Bloody lip. Happy heart."

On Thursday morning (December 16), Gaga took to her own Twitter to discuss her time in London, teasing her fans about her big shows in the city. She wrote, "London, I have never felt more grateful for little monsters, music, and creativity. I can't wait to blow the roof off the 02 arena tonight."