Batman an occasional ally and romantic interest), the Penguin, Ra's al Ghul, Two-Face, the Riddler, the Scarecrow, Mr. Freeze, Poison Ivy, Harley Quinn, Bane, Clayface, and Killer Croc among others. Many of Batman's adversaries are often psychiatric patients at Arkham Asylum. Batman's butler, Alfred Pennyworth, first appeared in "Batman" #16 (1943). He serves as Bruce Wayne's loyal father figure and is one of the few persons to know his secret identity. Alfred raised Bruce after his parents' death and knows him on a very personal level. He is sometimes portrayed as a sidekick to Batman and the only other resident of
Batman: The Animated Series actively involved in the management of Wayne Enterprises, without jeopardizing his secret identity. For example: in the episode "Eternal Youth", Bruce is shown angrily ordering one of his directors to cancel a deal with a timber company in the Amazon rainforest that had been made behind his back, threatening him with termination upon failure to comply. Kevin Conroy used different voices to distinguish between his portrayal of Bruce Wayne and Batman, a tactic used previously by Michael Keaton in Tim Burton's live-action films. Conroy based his dual-voice performance on the 1934 film adaptation of "The Scarlet Pimpernel". The series also