Tuesday, the four "American Idol" finalists perform rock songs with guidance from Slash, former lead guitarist of Guns N' Roses. Show starts at 8 p.m. on Fox.
Daughtry and No Doubt will sing on the 9 p.m. Wednesday results show.
Slash has posted frequent updates on social networking site Twitter since agreeing to mentor on "Idol." Recent posts included this promise: "I'm going to attempt to make 'Rock Week' on American Idol exactly that."
There's another reason fans are buzzing about Tuesday's show: Some Internet spoiler sites are reporting that in a twist to the usual "Idol" format, contestants will sing one solo tune and one duet with another finalist.
Would a Kris Allen/Adam Lambert duet be a train wreck or a showstopper?
Share your thoughts on our "Idol" blog, updated "live" throughout each show.