Batman: The Dark Knight Returns (film) arrested. Injured, Batman returns to the Batcave with Kelley, and allows her to become his protégée in spite of protests from his butler, Alfred Pennyworth. Batman has Kelley disguise herself as a Mutant, and she lures the gang to a sewer outlet at the West River. At the Gotham City Police Department, the Mutant leader murders the mayor during negotiations. Commissioner Gordon deliberately releases the leader, providing an escape from the building, which leads to the sewer outlet. Before the amassed Mutants, Batman fights the leader in a mud pit; the mud slows the leader, removing his physical advantage, and
Batman: The Animated Series as the Mad Hatter, David Warner as Ra's al Ghul, Michael York as Count Vertigo, Kate Mulgrew as Red Claw, George Murdock as and George Dzundza as the Ventriloquist. One of the series' best-known inventions is the Joker's assistant, Harley Quinn, who became so popular that DC Comics later added her to mainstream Batman comic book continuity. The Penguin underwent change for the series; his appearance was remodeled after the version seen in "Batman Returns", which was in production simultaneously with the series' first season. New life was also given to lesser-known characters for the series such as the Clock