Dr. Simon Barsinister

Peter Dinklage

Shoeshine / Underdog (voice)

Jason Lee

Dan Unger

Jim Belushi

Cad

Patrick Warburton

Jack Unger

Alex Neuberger

Molly

Taylor Momsen

Mayber

John Slattery

Riff Raff (voice)

Brad Garrett

Pollice Chief

Timothy Crowe

Police Officer

Mario Mariani

Polly Purebred

Amy Adams

Principal

Samantha Bee

Security Guard

Larry Vigus

Cop

Bates Wilder

Police Sergeant

Frank Ridley

Small Boy

Alexander 'Alex' Garde

Police Secretary

Diana Shneider

News Stand Guy (as Joseph Siriani)

Joe Siriani

Observer (uncredited)

John Franchi

Referee

Ezra Buzzington

Office Worker #1

Sujoy De

Office Worker #2

Michele Proude

Jay Leno

Jay Leno

Geek Worker

Albert M. Chan

Diana Flores

Susie Castillo

Supershep 1 (voice)

Phil Morris

Supershep 2 (voice)

Michael Massee

Professor

Bob Jaffe

Little Brown Dog / Supershep 3 (voice)

Cam Clarke

City Worker (as Bruce Serafin)

Bruce-Robert Serafin

Bulldog / Supershep 4 (voice)

John DiMaggio

Passerby

Lonnie Farmer

Crazy Dog (voice)

Danny Mastrogiorgio

Male School Teacher (as Tony Estrella)

Anthony Estrella

Astronaut (voice)

Jess Harnell

Office Worker

Susan Garibotto

Bomb Squad Officer

Malik McMullen

Police Chief

Tim Crowe

Old Man

Walter Covell

Housewife

Kate Lohman

Geek with Glasses

Lewis D. Wheeler

College Guy

Grady Justice

Fox Collar Lady

Rebekah Aramini

Cat Burglar Police #1

Joe Stapleton

Cat Burglar Police #2

Armen Garo

News Director

Daniel Kirby

Mother

Rena Maliszewski

Bomb Squad Officer #2 (as Robert Boehm)

Bob Boehm

Lyle

Gabriel Field

Police Artist

Harry L. Thomas

Capitol City Security

Adam McCarthy

Capitol City Cop

Roy Souza

Capitol City Cop

Tom Paolino

Hot Dog Contestant

Scott Dittman

Fireman (as Chris Ciulla)

Chris Andrew Ciulla

Goon #1

Joe Bucaro III

Goon #2

Stuart F. Wilson

Office Worker (uncredited)

Susan Garfield

Jack Unger (voice)

Michael Tyler Henry