"Gadget on the Brain" is the 22nd episode of the second season of Gadget and the Gadgetinis.
A microscopic implant has been detected in the brain of General Gastritas. It is suspected to be a M.A.D. mind control device and since he's about to be made Supreme Commander of the MegaPowers militaries (there's a running theme in this series of growing global unity and the disarmament of all weapons of mass destruction to make world peace possible), W.O.M.P. can't afford to take chances. So a volunteer is needed to be miniaturized by an experimental process and injected into the General's brain to remove the device. It is a one in a million chance of surviving the mission, so Nozzaire is happy to volunteer Gadget. Gadget, the Gadgetinis, and the Gadgetmobile are shrunk and injected into General's skull to face angry white blood cells who don't like intruders and miniaturised M.A.D. agents, ready to defend the mind controller. Just to complicate things further, the scientists made a miscalculation when they shrank them and they have only a few hours rather than days before they return to normal size.