Britney Spears spiced up her Vegas show on Tuesday by pulling Nicole Richie up on stage, tying a leash around her neck, and dragging her around on all fours.

The new redhead has been performing in a Vegas residency since the end of December and usually pulls a guy up on stage during that part of the show, but she couldn’t resist getting her old friend involved.

“Can we all give a round of applause to @NicoleRichie for playing along in the show tonight? U looked hot crawling on all fours ;),” she wrote on Twitter later.

A few new Spears tracks were released recently by producer Danja, who has worked with the singer on several albums. One of the songs was from her 2008 album Circus but ended up on the cutting room floor.

“More than anything, [Spears] nailed the energy and vibe that I wanted to capture on the track,” he said.

The other two tracks come from Britney Jean and Blackout.

Image via Wikimedia Commons