John Brown is a security guard for a science lab operated by robotics expert Brenda Bradford in Riverton, Ohio. He is the legal guardian of his 10-year-old niece, Penny and they have a dog named Brain. He hopes to be a police officer, but is denied from the force by Chief Quimby. The multi-millionaire tycoon Sanford Scolex attacks the lab, stealing valuable equipment for the "Gadget Program" and killing Brenda's father in the process. John, who is smitten with her, gives chase despite his co-worker Thelma warning him that the chase wouldn't end well and trying to convince him to lay off by telling him he's off duty at the moment . The ensuing car crash brings a confrontation with Scolex, who uses a victory cigar explosive to blow up John and his beloved Chevette, leaving him for dead. But in the fiery blast, a bowling ball in the back seat of his car flies into the air and through the sunroof of Scolex's limo, landing directly on and rapidly smashing his left hand. John, presumably deceased, is rushed to intensive care by Brenda. John is revived and rebuilt using electronic parts and is dubbed "Inspector Gadget". He is given lessons by a meditating guru at the lab in relaxing his body and getting a firm grip on the workings of his gadgets, which ends in failure when he accidentally grasps the guru's testicles with a little too much force. Despite some previous success in capturing two criminals, he is assigned with many community service jobs, such as crossing guard, litter patrol, and rescuing kittens. Meanwhile, Scolex's assistant Kramer builds a new, mechanical claw to replace his hand, and Scolex renames himself "Dr. Claw". Unlike the original cartoon series, his face is visible. He then tries using the stolen equipment to move a robot, but fails. When Sykes calls it a lemon, he has him put it on . But this fails too and he concludes that he needs Brenda's help. He hires her as his robotics specialist and is amused to discover that John is the "lucky duck they plucked for the Gadget Program." Later, he gets a copy of Gadget's chip and inserts it into the earlier robot, which he names Robo Gadget. John investigates Scolex, but while Gadget sees a moisture alarm, he overlooks an audio one and is captured in the process. After informing him about his plans, Dr. Claw takes his control chip and destroys it, leaving him "dead". He then sends Robo Gadget to destroy the city. While Sykes dumps Gadget's body in the junkyard, Brenda discovers through information given to her by Robo Brenda that Dr. Claw murdered her father. She and Penny race to save John. They discover them in the junkyard, and after Brenda kisses his cheek, he miraculously returns to life; showing that even though he is part machine, he still has a human heart. After a chase through the city between the Gadgetmobile and Dr. Claw's car, John battles Robo Gadget on the Roberto Clemente Bridge. Robo Gadget, despite his gadgets being more war machine rather than detective work, quite literally loses his head , and he tosses it in the river. Activating the "Go Go Gadget Chopper", he flies to the roof of Scolex Industries, where Dr. Claw prepares to make his escape with Brenda when Gadget comes around. While the helicopter hat is disabled and Gadget is lifted over a high drop, he launches the inside of a pen into the helicopter's cockpit, hitting the shutdown button on Dr. Claw's claw and crushing the controls. Brenda and Gadget crash to the plaza below, where police await to arrest him for all of Robo Gadget's crimes. Dr. Claw tries to escape, but is caged in by the Gadget Mobile. Sykes, a confused minion brought to the light by Penny, confesses alongside her that Robo Gadget was impersonating the real Gadget. John is made a hero in Riverton and earns Chief Quimby's respect. As Brenda and Gadget walk away, Dr. Claw yells out, "Arrivederci, Gadget! This is not good-bye. I'll get you next time, Gadget! I'll get you!" The film closes with Brenda kissing Gadget, with fireworks coming from his right foot as a sign of arousal, and with the Gadgetmobile chasing a red Volkswagen. The credits show Robo Brenda doing a crazed aerobics class, the headless Robo Gadget running around town, Sykes being congratulated at a minion recovery group, Penny speaking to Brain and the Gadgetmobile's computer screen thanking the audience for watching his movie, even though they called it Inspector Gadget. He says things are working out with the red VW, whom he married at a drive-thru chapel. He's also expecting a sub-compact he's thinking of calling, "The Love Bug", which is in no way a plug for the Walt Disney Company, although he's sure the little one will say, "I'm going to Disneyland!", when he's old enough. Lastly, he asks everyone not to leave the theater just yet, as all the people in the credits make him look good.