Outside of the eponymous protagonist, who’s known as Arthur Fleck before becoming a clown criminal, the only other character from the comics who’d been confirmed for Joker was Thomas Wayne, who’s being played Brett Cullen and will be depicted less sympathetically than usual.
Both of these casting updates come from Comicbook.com, confirming that these legendary DC Comics characters will play some kind of role in Joker.
With Bruce and Alfred now on the cast, it seems we’ll be peeking in on Thomas’ personal life rather than just see him as a public figure.