2. Adam Lambert, "Mad World"
Lambert's moody take on Tears for Fears' "Mad World" — done in the style of Gary Jules' piano cover for Donnie Darko — was a star-making one. He brought the theatrics that set him apart as a contestant but in a subtle way to match with the somber tone of the song, all while belting out the song for one of his strongest vocal performances on the show. Even Simon Cowell was on his feet at the end of it.