Matthew Broderick
John Brown / Inspector Gadget / Robo Gadget
Rupert Everett
Sanford Scolex / Dr. Claw
Joely Fisher
Brenda / Robobrenda
Michelle Trachtenberg
Penny
Andy Dick
Kramer
Cheri Oteri
Mayor Wilson
Mike Hagerty
Sikes
Dabney Coleman
Chief Quimby
D.L. Hughley
Gadgetmobile (voice)
René Auberjonois
Artemus Bradford
Frances Bay
Thelma
Mr. T
Richard Kiel
Famous Big Guy with Silver Teeth
Richard Lee-Sung
Famous Villain with Deadly Hat
