Jennifer Love Hewitt Liz
Bill Murray Garfield (voice)
Alan Cumming Persnikitty (voice)
David Eigenberg Nermal (voice)
Brad Garrett Luca (voice)
Jimmy Kimmel Spanky (voice)
Stephen Tobolowsky Happy Chapman
Debra Messing Arlene (voice)
Breckin Meyer Jon
Richard Kind Dad Rat (voice)
Nick Cannon Louis (voice)
Alyson Stoner Kid Rat (voice)
Jerry Hauck Cop
Eve Brent Mrs. Baker
Mark Christopher Lawrence Christopher Mello
Mel Rodriguez Security Officer
Juliette Goglia Little Girl
Neil Machlis Executive Producer
Jim Davis Comic Book
Michael Monks Deputy Hopkins
Joel Cohen Screenplay
Christophe Beck Original Music Composer
Crystal the Monkey Pet Monkey (uncredited)
Peter Hewitt Director
Alec Sokolow Screenplay
Bill Hoag Roy the Lodge Member
Dean Cundey Director of Photography
Ben Kronen Older Man
Barbara Anne Klein Stunts
John Davis Producer
Risa Bramon Garcia Casting
Michele Imperato Stabile Co-Producer
Evan Arnold Wendell
Angie Jones Animation
Mathew Krentz Compositing Artist
Dan DeLeeuw Visual Effects Supervisor
Peter E. Berger Editor
Daamen J. Krall Announcer
Glenn Derry Pre-Visualization Supervisor
Michael A. Stevenson Editor
Brennan Dufresne Casting
Alec Hammond Production Design
Brian Manis Executive Producer
Vanessa Campbell Miss Ace Hardware
Marie France Costume Design
Randee Reicher Dog Owner #2
Rufus Gifford Dog Owner #1
Susan Moore Dog Owner #4
Joseph Edward Taylor Frank
Ryan McKasson Dog Owner #3