In his first appearance, the Mad Hatter attempted to steal a trophy from the Gotham Yacht Club, but was foiled by Batman while he tried to rob spectators from a high society horseshow. The Mad Hatter disappeared afterwards. Later, a different, moustached Mad Hatter appeared, claiming to be his predecessor. This Mad Hatter first appeared in Detective Comics #230 in April 1956, and, unlike the original, was sane and sported a gaudy mustache. He was primarily a thief, apparently obsessed with completing his private collection of hats from all nations, cultures, and historical periods. He often constructed various weaponry concealed inside his hats like flamethrowers and buzzsaws. The headgear he wanted most was, of course, Batman 's cowl. In numerous attempts, he tried to unmask Batman. He was eventually successful after spraying the cowl with a radioactive substance causing Batman to remove it. No sooner did the Impostor Mad Hatter put it in his collection than Batman and Robin arrive. They had traced the cowl with their "super-sensitive Geiger-counter" in the Batplane.