Gearhead is Nathan Finch. While he was kidnapping and holding his boss' daughter for ransom, he runs afoul of Batman who rescues her. Unfortunately he wasn't able to save Nathan from falling to an icy death. Nathan Finch's body was discovered by two down-and-out people who take him to an unnamed underworld doctor. It turned out that Nathan wasn't dead and the doctor wanted his knowledge of cybernetics. Due to ravages of frostbite, the doctor removed his arms and legs and replaced them with cybernetic arms and legs. Nathan becomes Gearhead and develops his own cybernetic arsenal of removable body parts as well as a goal to exterminate Batman, whom he refers to as the "vermin".
No Man's LandEdit
He played a part in the Robin section of the No Man's Land crossover, in which he is one of a number villains competing for control of Gotham City's sewers. Without the use of Cybernetic arms and legs, he is forced into partnership with the thuggish Tommy Mangles, who carries around Finch's torso. The duo are iced by Mr. Freeze, a fate particularly frightening for Gearhead, given his origin.
Gearhead puts in an appearance in the comic mini-series Rush City, where he is physically attached to his car.
Powers and AbilitiesEdit
Gearhead possesses an arsenal a cybernetic weapons in his arms and legs, as well as spare limbs that he can swap out on the fly.
In other mediaEdit
See: Gearhead (The Batman).