Fluke

Matthew Modine

Thomas P. Johnson / Voice of Fluke

Nancy Travis

Carol Johnson

Eric Stoltz

Jeff Newman

Max Pomeranc

Brian Johnson

Ron Perlman

Sylvester

Jon Polito

Boss

Bill Cobbs

Bert

Federico Pacifici

Prof. Santini

?

Clarinda Ross

Jane, Tom's Secretary

?

Adrian Roberts

Night Guard

Bart Hansard

Day Guard

Deborah Hobart

Dogpound Vet

Libby Whittemore

Libby, the Housekeeper

Collin Wilcox Paxton

Bella

Samuel L. Jackson

Rumbo (voice)