Billy Crystal

as Mike (voice)

John Goodman

as Sullivan (voice)

Charlie Day

as Art (voice)

Dave Foley

as Terry (voice)

Sean Hayes

as Terri (voice)

Joel Murray

as Don (voice)

Peter Sohn

as Squishy (voice)

Julia Sweeney

as Ms. Squibbles (voice)

Nathan Fillion

as Johnny (voice)

James Kevin Ward

as Dad (voice)

Bobby Moynihan

as Chet (voice)

Cristina Pucelli

as Timmy (voice)

Kim Donovan

as Additional Voices (voice)