Carrie Underwood returns to the show that made her famous Wednesday night. She's set to perform "Undo It" on American Idol's season finale, five years after she won the competition herself. Since that time, Carrie has reached the top of the country world, scoring hit after hit and selling more than 10 million albums. Though Carrie has found huge success, most Idol winners haven't gone on to set the music world on fire.

So, what sets Carrie apart?  She says, "There's a lot that goes into it, and a lot of it has to do with luck and fans and God." Tuesday night's Idol finale also marks the last time SIimon Cowell will appear on the show as a judge.  He recently said it was apparent from the moment Carrie walked into her first Idol audition that she'd be a big star. Carrie's not so sure about that, though. After she won the ACM Entertainer of the Year trophy for a second time last month, Carrie said, "I don't think anybody could have predicted any of this."

Crystal Bowersox and Lee DeWyze are the two finalists competing for the American Idol crown on tonight's two hour and seven minute season finale, airing at 7:00 PM CST on Fox.