WARNING: The following contains spoilers for Batman: White Knight Presents Harley Quinn #4 from Katana Collins, Sean Murphy, Matteo Scalera, Dave Stewart, and AndWorld Design, on sale now.
Batman: White Knight Presents Harley Quinn has proven that Gotham can rely on Harley to help save the city in the Dark Knight's absence. With Bruce Wayne in jail, she's working with FBI agent, Hector Quimby, to solve a spate of murders tied to the Golden Age of film, as well as to Joker's past.
Harley knows he's dead, but Jack Napier has a copycat roving, which has put her into the crosshairs of the Producer and his knife-wielding Starlet. However, Batman: White Knight Presents Harley Quinn #4 reveals that Harley seeks Bruce's advice she makes a startling revelation regarding her role in the creation of the Joker.
Initially, Bruce tries to take the blame, but Harley admits that's not the case. In this franchise, even the Clown Prince of Crime himself blamed the Bat for turning Jack into a monster, but Harley tells Bruce she's the reason Jack Napier fell into that fateful vat of chemicals.
In this issue, Harley confesses that, after becoming infatuated with him for her academic research, she started listening to police scanners. She heard the ruckus at Ace Chemicals, decked out for the first time as a jester and headed over to talk Jack out of murdering someone he kidnapped for his mob boss. However, when he came to his senses, he wanted her gone since he cared for her. Harley was stunned as she had no clue Jack loved her, but she had to hide because Batman was seconds away. This led to Joker and Batman fighting, with Joker taking a bullet ricochet to the face and falling off a metal bridge into the vat of green acid.
The Caped Crusader got his hand but Jack wouldn't give him the other one as he slipped away, all because he wanted a distraction so Harley could escape. If he fell in, he knew Batman and the cops would have to tend to him, so there'd be enough time for her to flee. He didn't want her to get fingered as an accomplice or be painted as someone emotionally and professionally compromised based on her romantic feelings.
The heartbreaking moment comes when Jack, after being pulled out, yells at Batman and screams at her to go away. Harley knew, though, he was seeing her and talking to her in the rafters, telling her she couldn't save him. Ironically, this would be the birth of Harley as she knew the one way to get to him and babysit was to become his queen.
Bruce admits he knew Harley was there too but he always bet on her to do right by Joker and redeem herself someday, which she did. Even though Harley maintains her involvement in Joker's creation, Batman makes it clear that she's not the catalyst for his demise. As he puts it, Jack made his own choices and was always going to walk a tragic path. All that matters now is that Harley continues her redemption by being the hero both Bruce and Jack knew she could be.