Nicole Sullivan
Joan of Arc (voice) / Marie Curie (voice)

Will Forte
Abe Lincoln / Narrator (voice)

Michael McDonald
Gandhi (voice)

Christa Miller
Cleopatra (voice)

Neil Flynn
Carl (voice) / Julius Caesar / Carl (voice) / Julius Caesar (voice) / E-CyboPooc...

Donald Faison
Toots / Wally (voice) / Toots (voice) / George Washington Carver (voice) / X-Str...

Andy Dick
Mr. Sheepman (voice) / Mr. Sheepman / Thomas Edison / Sexual Education Officer (...

Debra Wilson
Reporter (voice) / Harriet Tubman / Eva Peron (voice) / Girl in Commercial (voic...

Sarah Chalke
Marie Antoinette (voice) / X-Stream Erin (voice)

Zach Braff
X-Stream Mike (voice) / Paul Revere (voice)

Joe Flaherty
Abe’s Foster Dad (voice)

Marilyn Manson
Marilyn Manson (voice) / Marilyn Manson (voice) (uncredited)

Michael J. Fox
Gandhi's Remaining Kidney (voice)

Mandy Moore
Mandy Moore (voice)

Luke Perry
Ponce de León (voice)

John C. McGinley
Creepy Trucker (voice)

Chris Berman
Chris Berman (voice)

John Stamos
John Stamos (voice)

Jack Black
Pusher / Larry Hardcore (voice)

Ashley Parker Angel
Ashley Parker Angel (voice)