This is probably one of the most controversial books I have on here. In The Killing Joke Joker shoots Barbara Gordon and then takes pictures of her nude, wounded form to drive her dad, Commissioner Jim Gordon, crazy. That’s the crux of the controversy, that wounding of a healthy young girl solely to further the plot. It’s a dark story, and it was never meant to be canon, but someone decided to do away with Babs and her role of Batgirl (Joker of course did not know she was Batgirl, the attack was because of her parentage). She was later reintroduced as one of the best characters ever, Oracle, though they took that away with another reboot.
I’ve read all the theories about the ending, about what Joker and his henchmen did to Barbara, about the women in refrigerators and all of it. I list this book because at the time it left a large impression on me, and one that has evolved over time. I still like this book, but now as an adult, I can appreciate the intended and unintended nuances to it.