Three young monsters — Ickis, Oblina and Krumm — attends an institute for monsters under a city dump and learn to frighten humans.
Charlie Adler
Ickis (voice)
Christine Cavanaugh
Oblina (voice)
David Eccles
Krumm / Snorch (voice)
Gregg Berger
The Gromble (voice)
Jim Belushi
Simon the Monster Hunter (voice)
Kath Soucie
Blorp 2+4 / Woman (voice)
Lacey Chabert
Girl (voice)
Michael Dorn
Borl / Chauffer (voice)
Bronson Pinchot
Deitrich Dunlap (voice)
Tim Curry
Zimbo (voice)
Shelley Duvall
Ocka (voice)
Beverly Archer
The Library Monster (voice)
Edward Winter
Dr. Buzz Kutt (voice)
Billy Vera
Slickis (voice)
Marcia Strassman
Harryette (voice)
Bill Fagerbakke
Carl (voice)
Charlie Adler
Ickis (voice)
Christine Cavanaugh
Oblina (voice)
David Eccles
Krumm / Snorch (voice)
Gregg Berger
The Gromble (voice)
Jim Belushi
Simon the Monster Hunter (voice)
Kath Soucie
Blorp 2+4 / Woman (voice)
Lacey Chabert
Girl (voice)
Michael Dorn
Borl / Chauffer (voice)
Bronson Pinchot
Deitrich Dunlap (voice)
Tim Curry
Zimbo (voice)
Shelley Duvall
Ocka (voice)
Beverly Archer
The Library Monster (voice)
Edward Winter
Dr. Buzz Kutt (voice)
Billy Vera
Slickis (voice)
Marcia Strassman
Harryette (voice)
Bill Fagerbakke
Carl (voice)
Charlie Adler
Ickis (voice)
Christine Cavanaugh
Oblina (voice)
David Eccles
Krumm / Snorch (voice)
Gregg Berger
The Gromble (voice)
Jim Belushi
Simon the Monster Hunter (voice)
Kath Soucie
Blorp 2+4 / Woman (voice)
Lacey Chabert
Girl (voice)
Michael Dorn
Borl / Chauffer (voice)
Bronson Pinchot
Deitrich Dunlap (voice)
Tim Curry
Zimbo (voice)
Shelley Duvall
Ocka (voice)
Beverly Archer
The Library Monster (voice)
Edward Winter
Dr. Buzz Kutt (voice)
Billy Vera
Slickis (voice)
Marcia Strassman
Harryette (voice)
Bill Fagerbakke
Carl (voice)