But at the core of her eye-winking gimmicks, and poppy tunes, is legitimate artistry. Her lyrics and song themes are multi-layered. They are both sassy and deep. They also show noticeable growth. And when she's on stage, Perry fires on all cylinders. Whether it's with her opening number, the ballad "Teenage Dream" or the fiery sex-charged "I Kissed a Girl," Perry can switch gears with precision.