Batman has never been to the Playboy Mansion. Despite what you may have heard.
As legend has it, the idea for the 1966 "Batman" show was sprung at a Playboy party—either at Hugh Hefner's mansion or one of the numerous clubs—where a television executive joined other revelers in watching the 1940s Batman movie serials as a lark. The image of suave, libertine gentlemen and scantily-clad Bunnies guffawing at the Caped Crusader and Boy Wonder in between slurps of Manhattans has entered the Batman lore, passed on from comic-con to comic-con.
Except it probably never happened. It's a myth—but with a grain of truth. And the true story is actually more interesting. Like so many others, Batman went to college in the 60s, and got a little crazy. And then nothing was ever the same.