James Woods (Dr. Phillium Benedict (voice)),
Dabney Coleman (Principal Peter Prickly (voice)),
Peter MacNicol (Fenwick (voice)),
Melissa Joan Hart (Becky (voice)),
Diedrich Bader (Guard #2 (voice)),
Dan Castellaneta (Guard #1 (voice)),
Rickey D'Shon Collins (Vince La Salle (voice)),
Jason Davis (Mikey Blumberg (voice)),
Robert Goulet (Mikey's Singing Voice (voice)),
Tony Jay (Dr. Rosenthal (voice)),
Ashley Johnson (Gretchen Grundler (voice)),
Andrew Lawrence (T.J. Detweiler (voice)),
Tress MacNeille (Lunchlady Irma / Ms. Lemon / Opera Director / Dr. Steinheimer (voice)),
Andrea Martin (Lunchlady Harriet (voice)),
Courtland Mead (Gus Griswald (voice)),
Ryan O'Donohue (Digger Dave / Randall (voice)),
Kevin Michael Richardson (Cop #2 (voice)),
Pamela Adlon (Spinelli (voice)),
Nicholas Turturro (Cop #1 (voice)),
April Winchell (Ms. Finster / Mrs. Detweiller (voice))