Barbara opens the door, and there stands Joker with the gun leveled at her gut. The gun goes off, *BANG* and... out pops one of those little flags with "Bang!" printed on it. After a beat Barbara turns to warn her dad but it's too late; the largest of the goons tackles her to the ground, shoving her through the coffee table. The other two subdue Gordon before he can get to his service revolver hung on the back of a chair; they beat him into submission, while the Joker calmly walks about the home giving one of his grand, theatrical, nonsensical speeches. The goons gather up an unconscious Gordon and make ready to leave at Joker's command, they don't want to be late for his master plan after all; Barbara, meanwhile, is still stunned because a 250lb-plus freak just speared her through a piece of furniture. Joker tells the big goon to "make sure 'daddy's little girl' won't be following us" and turns to walk out the door when...
BANG!
A solitary gunshot rings out. Joker freezes in the doorway, then slowly turns around to face the room. Barbara Gordon is lying on the ground in a pool of blood, moaning, while the big goon stands over her, smoking gun in hand, ready to deliver a second and fatal shot.
Joker. Is. LIVID. "WHAT THE F*CK DO YOU THINK YOU'RE DOING?!?"
The goon responds, "What boss? You told me to take care of her!"
Joker runs over and snatches the gun away. "I meant TIE HER UP, so she can't call her friends in blue, YOU GODDAMN MORON! I NEVER SAID TO SHOOT HER!!!" Joker stares down at Barbara for a moment. Lenny had recommenced the guy because they needed the extra muscle, said he was just smart enough to take direction and not ask questions. But the roided-up lummox was an amateur after all, and decided to go "off script" in the worst possible way. Joker closes his eyes, takes a deep breath, then sternly says "Out."
"B- but boss--"
Joker jerks his head around and glares at him. "OUT."
The goon makes a hasty exit, leaving Joker alone in the apartment with Barbara. She's still conscious, barely, and watching him as Joker walks over to the windows and shuts the drapes. He stands there with his back turned for a moment in total silence, and when he turns his entire demeanor has changed. His face is calm, placid, even... compassionate maybe? He walks over, kneels down beside her, and begins pulling at her clothes. She's thinking "oh god he's going to molest me" and starts weakly trying to fight back, but he just pushes her hands away and scolds her like a child. Barbara realizes what he's trying to do, and it freaks her out even more than what she thought: HE'S TRYING TO HELP HER. He's administering first aid, trying to stop the bleeding, checking for an exit wound, trying to make her comfortable. In fact, in checking her over Joker realizes that she's paralyzed, even before she does.
And then he starts talking to her, calmly rambling on about nonsense as he works over her at first it seems, and then she realizes that he's APOLOGIZING to her; that he's pretending to be sorry that this happened, that one of his new goons got overzealous and hurt her, which was certainly not his intention. At least, she thinks he's pretending, but if he's putting on an act then it's a very good act. Joker keeps repeating to her that he never intended for this, and that it's not only important that she understand it but that "HE" understand it, that she make him understand it; at this point, from how he's talking to Barbara, it becomes clear that Joker long ago worked out that she's actually Batgirl.
Joker finishes his ministrations, then produces a capsule of his Joker gas. She balks but he assures her that it's going to help with the pain, that it'll wear off soon, and breaks the capsule then waves it under her nose. He's right; the pain fades away, and she just feels giddy. Joker walks over to the telephone and dials 911, reports the shooting and requests an ambulance, then hangs up. He checks Barbara one more time (she's still conscious, but involuntarily chuckling softly), then walks to the door. He takes a breath, squares his shoulders, and when he turns around he's "the" Joker again: the consummate showman, the madman with a perpetual grin. He says something to her, in his customary dramatic flourish, then leaves her laughing as sirens wail in the distance.
...So yeah. Joker saves Barbara Gordon's life; paramedics and doctors both agree she would have bled out without the care she received. And after Barbara's recovery, she's conflicted; if Joker hadn't been there that night, she would have never been shot and paralyzed and forced to end her career as Batgirl (in my version, Barbara eventually recovers limited use of her legs but it's a career-ending injury), but at the same time if Joker hadn't been there she would have died. And, that night she saw a side of Joker that virtually no one had ever seen, with the exception of Harley Quinn. So, she's conflicted to say the least.
It all ties in to this idea that I had about Joker being this almost tragic figure, clearly deranged but not in the "pure and absolute evil" way he is now. The idea involved him being driven insane after being failed by every level of society, and after the "Red Hood" incident becoming this social anarchist showman whose crimes typically affect corrupt societal figures in Gotham, both legitimate and illegitimate, and DON'T involve open murder. He'd be a more multifaceted, fractured being: outwardly the showman and entertainer criminal, delighting his victims as much as scaring them; inwardly, the tortured artist and wounded soul, traumatized and victimized. Yet still, underneath that lurks... something dark. Something no one in Gotham ever sees come forth unless it's the last thing they see on earth.
Harley knows it's there. I was undecided as to whether or not she's seen it first-hand and full-on, but she's seen glimpses of it in their therapy and she thinks she can help him control it. She wants to help him control it, because she loves him, is in love with the "charming showman" and the "wounded soul" and, I think those sides of Joker love her too. I think there has to be something there, between them, because honestly the whole "battered spouse" thing Harley has going on gets overplayed and just makes her look bad. So, in my version, Harley loves Joker for who he is and thinks that by being with him she can make him better, so it's this kind of radicalized therapy treatment rather than Stockholm Syndrome. And Joker, I think loves her, and I think Harley believes that the "good" parts of him won't let the "bad" part of him hurt her, and for the most part she's right.
And Batman knows it's there, even though he's got nothing more than hunch to go on because in my version, the Joker's never been connected to or convicted of a single murder. People have been hurt, certainly, and there may have been some indirect deaths as a result of his "grand spectacles"; but he's never caught Joker say, slitting someone's throat, or blowing their brains out. People that get on Joker's bad side just... disappear. A week, a month, a year after Joker frowns at them... they just vanish. Sometimes a body will turn up, but it's too far gone and there are no tell-tale markings, no calling card that says "Joker did it!" The goon that shot Barbara Gordon? Eight months later, his corpse washes up on shore in the next county, victim of an apparent gangland shooting.
There's just this hunch that the "dark something" in Joker exists; sometimes, Batman will catch a glimpse of it, this monster lurking under the white skin; but then, it's gone as quickly as it surfaces, like a long black fin breaking the ocean's surface, then sliding deep below.