Spoiler warning: If you haven’t yet seen Joker and plan on doing so, now’s your chance to stop reading. The rest of this story will be littered with movie plot points and spoilers. You have been warned!
- In Joker, Thomas Wayne (Batman’s father) and Penny Fleck (Joker’s mother) are key characters.
- Penny claims that Thomas is actually Arthur’s father.
- The movie wants you to guess for yourself who’s telling the truth.
Within the world of Joker, the line between reality and delusion is delicately toed throughout the movie’s two-hour runtime. Notably, viewers are led to believe that Arthur Fleck (Joaquin Phoenix), who becomes the titular Joker, is in a romantic relationship with his neighbor Sophie Dumond, played by Zazie Beetz. This is later revealed to be all inside his head.
But perhaps the movie’s biggest twist is the possible connection between Arthur and Bruce Wayne, as in his arch-nemesis Batman. Earlier in the movie, Arthur notices that his mother, Penny Fleck (Frances Conroy), is obsessed with a local businessman named Thomas Wayne (played by True Detective’s Brett Cullen). When he opens a letter she’s addressed to him, he sees a handwritten note that describes Arthur as Thomas’ son, suggesting that the Joker and Batman are half brothers. But is that really true?
According to Penny, Arthur was born of an affair she had with Thomas when she worked for him. She said in a flashback that Thomas’ wealth, power, and influence helped to produce the claim and paperwork that Arthur was adopted.
But according to Thomas, Penny was mentally ill when she worked for him, and the claim that their sons are brothers is a delusion. At one point, Arthur does visit Arkham State Hospital and reads his mother’s file, which says that she adopted him as a child and an abusive boyfriend took advantage of both her and Arthur when he was an infant/toddler.
At the end of the day, there’s more evidence that Thomas is telling the truth. Not because he’s a particularly upstanding person—he’s presented as the antagonist, and a quasi-villain of the movie—but when Arthur goes to the Wayne estate and meets Bruce and, eventually, Alfred, even Alfred says that Penny was unhinged.
Now, Joker presents a different reality, so we can’t be certain that this version of Alfred (played by Douglas Hodge) shares the same noble and loyal nature that the Alfreds played by Michael Caine and Jeremy Irons in the past. But given the history of the character, it’s enough to convince us that’s the truth—at least for now.