Ellen Degeneres celebrated her 55th birthday last week, and Katy Perry was on-hand to liven up the Ellen show. Instead of singing for the president however, Perry covered her famous bosom with a vest as she dressed in drag.

Perry donned a Richard Dawson-esque suit and bowtie as she impersonated a game show host, complete with creepy 70s moustache. She and Degeneres invited audience members to play “Grab Ellen’s Bust,” a simple quiz show that tested contestants’ knowledge of Ellen trivia.

Though a cross-dressing Katy Perry might sound entertaining, the highlight of the event is actually one of the audience members invited to be a contestant. Watch as she loses her mind when Degeneres touches her in an attempt to prevent her from falling over: