Aiken, who played a Jan. 18-May 4 stint in the Tony-winning musical, reprises his role as Sir Robin through Jan. 4, 2009.
Aiken joins a cast that currently features Michael Siberry, David Hibbard, Tom Deckman, Rick Holmes, Bradley Dean, Wally Dunn and Merle Dandridge as Lady of the Lake.
In a previous statement Aiken joked, "Since leaving Spamalot in May, jokes have just not been funny. Food has lost its taste. The grass is no longer green — the sky no longer blue. And, babies won't stop crying!! I'm so excited about coming back to the funniest show in the world!"
Aiken — who was bested by Ruben Studdard during the second season of "American Idol" — has gone on to sell more than six million albums, co-author a best selling book ("Learning to Sing: Hearing the Music in Your Life") and play six sold-out concert tours. He was a focus of the short-lived Off-Broadway musical Idol: The Musical and has appeared on "Ed," "Saturday Night Live" and "Scrubs."
Spamalot features a book and lyrics by Eric Idle, music by John Du Prez and Eric Idle, direction by Mike Nichols, choreography by Casey Nicholaw and is based on the screenplay of "Monty Python and the Holy Grail" by Monty Python creators Graham Chapman, John Cleese, Terry Gilliam, Eric Idle, Terry Jones and Michael Palin.
The musical tells the tale of King Arthur and his Knights of the Round Table on their quest from God for the Holy Grail — with a short stop in the dazzling Spam-filled land of Camelot.
Spamalot earned the 2005 Tony Award for Best Musical and took home honors for direction (Mike Nichols) and one of its stars (Sara Ramirez).
Spamalot celebrated its third anniversary on Broadway March 18.
On Broadway Spamalot plays Tuesday-Friday at 8 PM, Saturday at 2 and 8 PM and Sunday at 2 and 7 PM.
For more information visit www.montypythonsspamalot.com.