TVSquad

Alan Alda returns as Jack Donaghy's dad tonight on 30 Rock for the show's season finale, "Kidney Now." The plot finds Jack trying to put together a benefit concert for Alda, who is in need of a kidney. That, of course, means the ep will be loaded with appearances by famous musicians.

Guest stars include Elvis Costello, Mary J. Blige, Sheryl Crow, Maroon 5's Adam Levine and Clay Aiken. The clip below reveals some shocking truths about some of these famous crooners, including Aiken's relation to NBC page Kenneth Parcell.



Some might give 30 Rock a hard time for strutting out the guest stars more than any other show lately, but I don't mind. As this clip reminds us, the show continues to be one of the funniest things on TV. I'm already loving the fact that Clay Aiken is Kenneth's cousin (it just makes perfect sense, doesn't it?) and Elvis Costello is really an international art thief. And if anyone can make someone like Adam Levine funny, it's gotta be Tina Fey.

The finale airs tonight after My Name is Earl. It's the last new 30 Rock we'll get for months, so soak it up.