"I feel very honored to be a part of the Festival of New American Musicals, an organization that helps foster and inspire young artists like myself to create the next generation of new, exciting musical theatre," said Criss in a previous statement.

The 3 PM closing party, held in songwriter Eric Vetro's private garden, features songwriters and performers previewing their next musicals.

Scheduled to attend and perform are Rita Wilson (Chicago), Marissa Jaret Winokur (Hairspray), John Stamos (Bye Bye Birdie), Kristen Bell (The Crucible), Nia Vardalos (Chance & Chemistry), songwriter Desmond Child, Graham Phillips (13), David Burnham (Wicked), lyricist David Zippel, James Carpinello (Rock of Ages), singer-songwriter Sophie B. Hawkins, Amanda McBroom (Seesaw) and Nolan Gerard Funk (Bye Bye Birdie), among others. Also, Drew Carey (Hollywood Bowl's Hairspray), Wayne Brady (Chicago), Jeff Davis and Chip Esten will take suggestions from the audience to create an improvised short musical in the style of "Whose Line Is It Anyway?"

The 2011 Festival of New American Musicals, under the direction of executive producers Marcia Seligson, Bob Klein and Linda Shusett, presented 35 new musicals in theatres, colleges, high schools, middle schools, elementary schools and community centers across the Southland. Its mission is to help build the next generation of musical theatre audience and support.

Criss will succeed Daniel Radcliffe for a three-week stint in How to Succeed in Business Without Really Trying when he steps into the role of ambitious window washer J. Pierrepont Finch Jan. 3-22, 2012. Criss plays the role of Blaine, the openly-gay Warbler at Dalton Academy, on Fox's "Glee." Prior to "Glee," he was best known for his portrayal of Harry Potter in the YouTube hit, "A Very Potter Musical." For more information and tickets, visit www.lafestival.org.