Filmmaker Kevin Smith revealed that Todd Phillips’ Joker had an alternative ending that was even more horrifying than the one that made it into the final cut of the film. Speaking on his Fatman Beyond podcast on YouTube, Smith revealed that there was a version in which Joaquin Phoenix’s Joker was the one who killed Thomas and Martha Wayne in the alley outside the movie theatre before, and this is the truly horrifying part, killing young Bruce Wayne (and therefore also that universe’s Batman).
At around the 16:30 minute mark, Smith says, “Originally, the ending in the hospital was different. He’s in the hospital and he laughs, chuckles, and he says, ‘I was just thinking of something funny.’ What was supposed to happen was you flashed back to the death of Thomas and Martha Wayne and it was [Joker] killing Thomas and Martha Wayne and the boy was screaming and crying and [Joker] turned to walk away and he turned back, shrugged, and shot the kid. Credits. What the fuck man!”
Smith continues to explain that the alternate ending would have resulted in a universe without Batman, “This world has no Batman, it's just all fucking Jokers,” he says.
Of course, Smith isn’t sure if what he was told is completely true, saying that he hopes it is but that his information could also be “completely wrong.” Perhaps Todd Phillips or Phoenix will come out to confirm or deny the existence of the alternate ending. Until then, watch Smith’s podcast above.