During an interview with Empire Magazine, Killing Joke producer Bruce Timm and Joker voice actor Mark Hamill, shared some of the difficulties of adapting the story film. In particular, both Timm and Hamill cited how dark the story was.
Timm: “The thing about The Killing Joke is that it was probably the darkest story that had ever been told with those two characters up until that time.”
“I mean the idea of adapting this story always kind of terrified me, because of how relentlessly grim and bleak it is. And what happens to Barbara Gordon in the story is very controversial to this day.”
Hamill: “Even that surprised me, how edgy the Batgirl material was. This is not your father’s Batman. The one regret I have is that if I was nine years old, there’s nothing I would rather see more, yet it really isn’t for kids. I hope people understand when they say it’s R-rated, they mean it.”
Timm also spoke about how the film had been in production since before the release of Watchmen, but had been haulted twice due to Watchmen‘s poor reception and the shooting during the Dark Knight Rises.
This is actually the third time that The Killing Joke came up for production. The first time, it was because we had told the home video department that chances are if we do this story, it’s going to get an R rating. This was years ago, but they said, “We’re okay with that, but we’re going to kind of hedge our bets monetarily.” The idea was because the source material was not really long enough to do a full movie, we were going to do a shorter movie at a lower price point, so that would hopefully offset the loss of sales that we would have by the fact that it wouldn’t be an all age title.
But right around the time we were ramping up, the Watchmen movie was released and underperformed. Everybody kind of took a step back and said, “Well, maybe the time’s not right for an R-rated superhero movie, so put it on the shelf.”A couple of years later, it came up again and we even had started production with character designs and stuff. But then that horrible shooting at the Dark Knight Rises theater happened and everybody got nervous again about it, because of gun violence, so we put it back on the shelf. Go forward a couple of more years and it came up again.”
Hamill considers himself a Killing Joke purist and even wanted the adaptation to be a word for word audio book with sound effects and music, but it simply would not have been commercially viable.