The Elizabeth Arkham Asylum for the Criminally Insane, commonly referred to simply as Arkham Asylum, is a fictional psychiatric hospital in the DC Comics Universe, usually appearing in stories featuring Batman and often the Joker.
Arkam Asylum first appeared in Batman vol.1 #258 - “Threat of the Two-Headed Coin!” which was release in October of 1974.
Mark Hamill has voiced the Joker for almost 20 years in cartoons and video games, and has been hiding Arkham in his name all along.
Mark Hamill is THE Joker.
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