Jack Napier, also known as the Joker, is a fictional character introduced in the 1989 superhero filmBatman, directed by Tim Burton. Primarily portrayed by Jack Nicholson, the character was based on the DC Comics supervillain the Joker.^[1] His name is a play on the word Jackanapes, as well as a reference to the names Jack Nicholson and Alan Napier, the latter having portrayed Alfred Pennyworth in the 1960s Batman TV series and having died the previous year.^[2][3] This depiction is notable for being one of the first adaptations of the character to have a distinct first and last name, as well as one of the few instances which show his origins. This iteration of the Joker is a psychopathic gangster who serves as the right-hand man of Gotham City crime boss Carl Grissom until he is disfigured following a confrontation with the vigilante Batman; his disfigurement drives him insane, and he becomes a costumed criminal obsessed with "out-doing" the Dark Knight, who he believes is getting too much press.

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