After the real Mad Hatter had been sent to prison following his debut appearance, an Imposter Mad Hatter who claimed to be Jervis Tetch appeared. 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. The headgear he wanted most was, of course, Batman's cowl. In numerous attempts, he tried to de-cowl Batman. After many tries, he was successful, after spraying the cowl with a radioactive substance causing Batman to remove it. No sooner did the 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.