This first time I read Batman: Killing Joke, I was barely a teenager. I couldn't make heads or tails of it. Why is everyone in the Batman world so intense? The moody but well meaning Batman I knew had turned outright grim. The graphic novel (correct usage!) (this was actually a graphic novel, not a trade paperback) contained sexual violence and gruesome imagery, and it all hinged on an existential crisis. I wondered if the philosophical discussions between Batman and Joker were canon; isn't Batman supposed to make us happy? Sure the guy is a little sour, but he's still fun, right? Nope, writer Alan Moore and artist Brian Bolland seemed to be saying. We should be seriously worried about his mental health.
I was disturbed. I thought it was cool that I was disturbed. I was, as I said, barely a teenager. Alan Moore has since disavowed the book, declaring it a poor story that kicked off the gritty, cynical era of super heroes, and from which the comics industry took many years to recover. For my part, I don't know how I feel about an 2D animated version of this story, featuring Kevin Conroy and Mark Hamill, who have voiced the all ages Batman and Joker in multiple TV series, movies and (slightly darker) video games for decades.
Even if The Killing Joke is rated R, it has a lot more in common with the gentler version of Batman than it doesn't. The whole family may end up watching by accident, and let's be clear, not everyone in your family will enjoy seeing poor Commissioner Gordon stripped of his clothes and forced to endure the worst carnival ride of his life. I can already hear your grandmother, who you invited to watch with you, saying “Whaaaaaat? I thought this was Batman, not some bloody, S&M freak show!” “Dear God, what are they doing to Barbara Gordon?” Your Aunt Mildred scream before she gets the vapors and faints.
“I read this book before anyone wanted to make it into a movie. I'm more knowledgeable,” you will say with a knowing smirk, as Batman and Joker writhe in hysterics over the insanity of their sick lives.