Warning: If you haven't seen The Batman yet, spoilers follow from this point on.
As many will already be aware by now, Eternals actor Barry Keoghan does not play GCPD officer Stanley Merkel in the movie as was initially reported, but a mysterious character credited as “Unnamed Arkham Prisoner." Of course, you don't need to be the world's greatest detective to figure out that this guy was actually The Joker, and director Matt Reeves has now made it official.
During an interview with IGN, the filmmaker revealed that those leaked set photos featuring Keoghan in a police uniform were indeed faked in an attempt to preserve spoilers from getting out.
"When you're making a movie like this, you want it to be different, you want people to feel like they're having a special experience,” he said. “And then for me, when you're going to the cinema you want some level of surprise. I think one of the things I was worried about was speculation while we were making the movie, that we would be exploring the character that we ended up exploring. So we started thinking what we could do to throw people off that scent. This idea of making him Stanley Merkel was exactly that, because the police force is actually a big part of the story so it seemed credible that we could be doing that.”
Unfortunately, word did eventually get out that Keoghan was playing the Clown Prince of Crime, although it was treated as an unsubstantiated rumor for quite a while.
Keoghan only appears in a brief scene with The Riddler (Paul Dano) towards the end of the film, but Reeves recently revealed that another sequence featuring The Joker was cut, and has now shared some intriguing new details. As it turns out, Batman (Robert Pattinson) was originally going to pay a visit to his old enemy in Arkham to ask for his help in stopping Gotham's relentless serial killer.
“He goes to see another killer that he's clearly had an experience with in these first two years. And this killer in this story is not yet the character that we come to know, right? So everybody's in their infancy. So in the comics, these characters often declare their alter egos in response to the fact that there's a Batman out there. And so here, we have a Joker who's not yet the Joker.”
This suggests a Clarice Starling/Hannibal Lecter-like dynamic between the characters, and it's a real shame the scene didn't make the theatrical release. There's a good chance we will get to see it on the Blu-ray, though.