Gadget - Inspector

: Gadget’s highly intelligent 10-year-old niece. She is the true mastermind who uses her high-tech Computer Book and Video Watch to solve every case behind her uncle's back.

: The unseen main antagonist and leader of the criminal organization M.A.D. He is always accompanied by his pet, M.A.D. Cat , and is known for his growling catchphrase: "I'll get you next time, Gadget! NEXT time!" . Inspector Gadget

: Their faithful dog who serves as Penny's secret field agent. He often disguises himself to keep Gadget out of trouble, only for Gadget to mistake him for a M.A.D. agent and try to arrest him. : Gadget’s highly intelligent 10-year-old niece