The Reason

Part 2

A/N: All characters belong to DC Comics. The story occurs between Heroes in Crisis #5 and #6.

"Superheroing… I tell ya. Ya learn something new every day."

Batgirl was a patient woman. It was something she had learned by having a police officer as a father. It took a lot of persevering in order to fool a man who was used to detect a lie from a hundred yards away.

Yet, Harley was testing that resolve. It was the voice, probably, a sound that was like having honey poured into her ears in order to attract a million angry, buzzing flies.

"Focus, Harley, please," Batgirl said as the two of them landed on the rooftop of Gotham's First Bank. Or so she thought. It was hard to identify landmarks from above.

"I'm learning!" Harley hollered before bursting into song. Something about fruits, bats and cookies.

Patience, Batgirl thought. She wanted to get to the bottom of Sanctuary's crimes, even if it meant risking her own sanity. She owed it to Wally, to Roy, to Ivy and all of the others.

She was proud of herself. She really was. Batgirl had found the suspect before Batman did, and he was supposed to be one of the best detectives in the world and the universe, even. How had Harley evaded him, Superman and Wonder Woman was beyond her.

"And the cookie ate the fruit, and then the fruit ate the bat!"

Batgirl's experience with Harley was limited, probably because of Bruce's own design. He probably believed the further Barbara stayed from anything Joker related, the better for her. If it weren't so controlling and patronizing as hell, it could almost be sweet. Still, she remembered reading Bruce's assessment of Harley and, while it didn't paint her as mentally healthy, it didn't portray her so scattered, so unhinged. So broken.

Harley's physical prowess was spot-on, however. The had been running, jumping and swinging from rooftop to rooftop and Harley wasn't even breathing hard, much less sweating or getting tired. Bruce's report mentioned the possibility of Poison Ivy altering Harley's DNA at some point in their partnership and turning her almost meta-human, theoretically.

The way Harley cleared a 20-foot chasm between two buildings with zero effort wasn't theoretical at all.

"Say, if I hit him with my hammer and he stops moving for, like, forever, is that murder?" Harley asked after Batgirl used a lifeline to clear the jump between the two buildings.

"Yes, Harley, it is murder," Batgirl felt the need to rub her temples. "Have you suffered any head injury lately? Inhaled something weird? Eaten something that was glowing?"

"Nope, nope and nope," Harley grinned, but it was a fake smile. It was a practiced reaction, the proper response to human interaction, but it looked like a grotesque mask that covered the pained face of a young woman who didn't know who she was anymore.

"I do feel like my head is in a fuzz, ya know," she continued, the grin on her face faltering. "It's like, I'm on the car but someone else is driving. She looks like me but she doesn't drive like me. Not that I'm great with cars, or wheels, or knowing where I'm going."

"Harley, wait," Batgirl said, hurrying up in order to stand next to Harley and put a hand on her shoulder. "I need to know that you're with me, like, really here."

Harley looked at Batgirl, and her blue eyes did not seem to reflect any sort of understanding. After tense seconds, a look of comprehension appeared on the white face and Harley nodded.

"I have to be sure, Harley," Batgirl said, hoping she wasn't playing with fire by letting her guard down. "No killing, Har, no hurting, no maiming, no attacking Booster. We need to know what really happened and he needs to be awake and unhurt in order to tell us. Are you with me?"

"I'm not stupid, girl bat," Harley gently removed Batgirl's hand from her shoulder. "I'm on the driver's seat now, and I will be. For a while."

"No murder, Har," Batgirl repeated, feeling uncertainty for the first time that night.

"No murder," Harley nodded. "Cross my heart and hope to, ya know."

"Good. We're ahead of the others and I want to keep it that way," Batgirl started walking but this time, Harley stopped her by placing a hand on her shoulder.

"You mean Batman, Wonder Woman, and Superman?" Harley asked, looking around, almost as if she expected them to show up at any moment.

"Exactly. I can explain to Superman and Wonder Woman, but good luck trying to make Batman understand why I'm working with you," Batgirl shook her head.

"Kinda high-strung, our Bats," Harley took her hand away from Batgirl's shoulder. "Such a fascinating personality, from a strictly medical point of view, of course."

"I don't think there's anything fascinating about it," Batgirl muttered, "and we shouldn't be wasting time talking about it. We have to hurry."

"You mentioned something, back in the mirror house, about how he sees you," Harley said, and Batgirl cursed herself. She had to ask her to focus, right? It would have been easier to deal with crazy Harley instead of psychiatrist Harley.

"Har, it doesn't…"

"Broken, you said," Harley went on. There was no way to stop her mind now that she had focused on something. "Scarred, scared. A consequence of his failures. Something to do with Mr. J?"

"Harley, come on, we don't have the time to analyze…"

"Failure, Batgirl," Harley interrupted. "What if we fail? What if we don't fix anything after finding Booster? What if we fail by trying to do the same things Batman and you heroes do, time after time?"

"I don't like where this is going," Batgirl said, her mind quickly running an inventory of the weapons at her disposal. She wondered if she would be able to take on Harley on her own.

"You forbade killing, girl bat, but," Harley stood straighter and fixed her blue gaze on Batgirl's green eyes. "I guess I don't have to explain it all the way right? Exposition only works on movies and tv. Maybe we should kill Booster now and prevent any other tragedies down the way."

Harley crossed her arms and looked away, leaving Batgirl speechless for a change. They remained in silence for a while, until Harley shook her head and leaned out of the building's ledge, ready to jump.

"So you think that's the answer?" Batgirl finally blurted out, stopping Harley. "Let's kill every criminal so he or she doesn't hurt anyone again. Do you know what would happen then?"

"No more broken or scared girls," Harley answered, not looking back at Batgirl.

"Maybe," Batgirl said and walked until she stood next to Harley, "or maybe you could cause more damage. Have you thought about it?"

"Tell me then, why hasn't your precious Batman killed the Joker? Because he's so high and mighty? Because he feels the need to always be better than anyone else? Because he likes to save scared, broken girls like us?"

Harley was mad. There was no doubt about it. Something in the conversation had pushed buttons she probably wasn't even sure existed.

"Physics," Batgirl suddenly replied, shocking Harley, for a change.

"What the what?" Harley tilted her head, the dangling sleeves of her cap swinging back and forth.

"Simple physics, Har," Batgirl said as she approached the edge of the building and sat down, her legs swinging above the abyss. "Sit down; we do have time for this story."

"I thought you said we were in a hurry," Har placed her hands on her hips.

"Sit down, Quinn," Batgirl replied. "This is important."

Harley sighed but did as was asked.

"I was also confused by it at first," Batgirl said once Harley had sat down. "What did physics had to do with it? It was simple, shoot the shooter, kill the killer, right?"

"Seems like black and white to me, girl," Harley snorted.

"Now, let's look at it from another angle," Batgirl continued. "All those years ago, when he first put on the costume, Batman fought the regular kind of criminals: burglars, thieves, rapists, murderers, the works. Nothing out of the ordinary, right? But after a while, what happened? Other guys began dressing up, just as he did. Catwoman, the Joker, Two-Face, the Riddler, they all started wearing colorful costumes to fight back against the man the media had started referring to as the Batman."

"So it's our fault he feels responsible for the Joker?"

"No, look, listen to me," Batgirl smiled. "The criminals reacted to Batman's appearance, changing, adapting, and becoming something that could fight back against the newest threat. Now, thinking in terms of physics, what does that remind you of?"

"I'm a doctor, girl bat, not a physics major," Harley said, sounding truly interested. "I don't quite remember high school, you know?"

"' For every action, there's an equal and opposite reaction', Har," Batgirl explained. "It's Newton's third law of physics. Batman pushed one way, criminals pushed back with the same force but in the opposite direction. Then Batman pushed harder, making them retaliate, and so on. Am I making sense?"

"Yeah. Yes, you do," Harley said, her eyes looking into the distance.

"Now, imagine if he killed the Joker. What kind of force would that produce? Once their lives are at risk, what would they be willing to do? Who would pay the price? I think most criminals are afraid of something, whether they know it or not. Amplify that fear and, well, you're a doctor. I don't have to explain the human mind to you."

"Right, a primitive response," Harley sighed. "Physics. Wow. And here I thought he just got his kicks out of sending us to Arkham."

"Is it that bad?"

"It's terrible for the doctors, now imagine what it's like for the inmates," Harley chuckled. "Guess it beats the chair, though."

"No death penalty in the state, Har," Batgirl smiled again. "And I guess you would never get sent to it. Getting caught by a masked vigilante that operates outside the law certainly grants you some leniency."

"Again, doctor, not lawyer," Harley glared at her. "But it would explain why, after everything he's done, Mr. J has not gotten the death penalty here or anywhere else."

"Good lawyers, I guess," Batgirl shrugged. "Even if it doesn't seem fair. Sorry."

"Don't be sorry," Harley sighed. "I'm crazy but I'm not stupid. Mr. J is, and always will be, a monster."

"Booster is not a monster, though, and I guess I don't have to tell you what sort of force would be expected if you killed him," Batgirl said, bringing the focus back to their mission.

"I know," Harley replied, her face showing a mixture of sadness and understanding. "But if he did it, if he killed Pam, then… I don't know, girl bat, I would face all the physics in the universe to make him pay."

Batgirl understood, even if she would never accept it. She hoped she would never have to face a similar situation. For a moment, the two of them agreed to disagree and were glad to do so. The moment was fleeting, as the mask of madness over Harley's face surfaced again and the light in her eyes disappeared.

"So, if I slay Booster, does that mean I will always go to Arkham? Because the police can't get me and it's always some bat-themed kid who turns me in?" She asked.

Batgirl sighed. Harley was slipping back. It had been good while it lasted.

"No killing, Har. Come on, we already went through this," Batgirl said, annoyed at how Harley's sanity had again left the building. Or the rooftop, whatever the case may be. It was time to get moving again.

"Slaying is a different word," Harley said as Batgirl stood up from the edge. "Don't tell me it also means killing."

Batgirl felt like crying. She had witnessed a smart woman go back to the prison inside her mind. It wasn't fair. Harley deserved better, even if she was morally challenged.

Harley stood up as well, took several steps away from the edge and sprinted towards it, leaping into the abyss while singing again about fruits eating bats and cookies. Batgirl sighed. It looked like it was going to be a very long night.