I always thought that they intentionally leave the Joker's background uncertain and different stories because of the Joker's insanity. But I don't follow the comics that closely. Question: In the Batman movie, the Joker's real name was Jack Napier. Is this his real name in the comics, or is it different, or uncertain? I thought that someone who is a bigger Batman comic fan than I once told me that they had more than one 'real name' for the Joker, meaning they all are probably fakes.