Narrator
Joe Leahy
Freakazoid
Paul Rugg
Debbie Douglas
Tress MacNeille
Sgt. Mike Cosgrove (voice)
Edward Asner
Dexter Douglas (voice)
David Kaufman
Professor Jones (voice)
Jonathan Harris
—
Larry Cedar
—
Frank Welker
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Jeff Bennett
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Rob Paulsen
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Ricardo Montalban
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Maurice LaMarche
—
Jess Harnell
—
John P. McCann
—
Norm Abram
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Bebe Neuwirth
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Stephen Furst
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Corey Burton
—
Stan Freberg
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Tim Curry