Watch Katy Perry crash parties in 'Birthday' video

Never one to shy away from a costume change, Katy Perry plays a clown, an aging dancer, a Bar Mitzvah MC, an animal expert and a princess in the music video for her latest single "Birthday." The central conceit of the video is that an unrecognizable Perry wreaks havoc at a series of real-life parties, including one man's 90th birthday celebration. "GUYS, PREPARE YOURSELVES cuz it's time to bring out the big balloons and #MakeItLikeYourBirthday!" the 29-year-old singer tweeted before the video's release. According to TMZ, some people were genuinely appalled by her appearance at a 5-year-old's party, where she dressed up like a clown and faked a car accident.