A video has emerged from the filming of Warner Bros.'s Joker film starring Joaquin Phoenix, with Phoenix in-costume as part of a scene on a Gotham subway. The video was filmed by Hollywood Pipeline, who shared it on YouTube:
If you look closely, you'll see some of the actors are holding signs for and against Thomas Wayne running for Mayor of Gotham. Brett Cullen was recently announced as playing that role.
Joker is currently in production for a planned October 4, 2019 theatrical release.