The initial portion of the movie, roughly the first half-hour, felt like a misstep because Barbara’s character was so irritating. I honestly couldn't grasp the purpose of including that sequence, especially considering the film is supposed to focus on the Joker. Even Mark Hamill’s last performance as the well-known antagonist wasn’t enough to redeem the picture. However, I did find the concluding joke somewhat entertaining! Aside from those points, the narrative could have been more skillfully developed.

Source on TMDB