ABC
Leona Lewis
Simon Cowell's protégée trotted out her smash hit "Bleeding Love." And it apparently made her "Happy," because she was back the next season, too.
ABC
Jennifer Hudson
The Oscar winner didn't need to sweat through 12-hour rehearsals as a contestant to reveal a bangin' new bod.
ABC
James Blunt
Who doesn't want this guy serenading the room with "Carry You Home" at some point? Coincidence: ex Petra Nemcova ended up being a contestant a few seasons later.
ABC
Avril Lavigne
The "Complicated" singer performed her signature tune.

