Comic concept: Christmas Eve. Nightwing is on a rooftop in Bludhaven surveying a mostly quiet street.
*whumpf* behind him.

It's Batman. https://twitter.com/CelticAnarchy/status/1293041965676797952

Nightwing: oh no, what happened, why are you here?
Batman: Gotham's totally quiet. The gangs always observe a ceasefire for Christmas. Had a look around before I came to you. Looks like the same thing is happening in Bludhaven.
Nightwing: aaaand...

Batman: aaaand...

He produces a box. "Kane's Pizzeria."

Batman: Brought you your favorite.

[several minutes and some slices of pizza later]

Nightwing: So... how's Jason?

Batman stops in his tracks, sighs, and puts his piece down.

Batman: He's doing... better. Not great, but better.

Nightwing: You're doing a great thing for him. He really needs all the help he can get after... You know.

Batman: I wish I could do more. When Joker gets in your head, he *gets in there*.

Nightwing: Well, why don't you ask Tim to h-

Red Hood: HEY, I HEARD THAT.

They both look up. Red Hood is on the wall above them.

Red Hood: I don't like it when people talk about me behind my back. Now I have to do this.

He reaches into his pack. Both Batman and Nightwing tense up.

Red Hood produces a bottle of sparkling cider.

Red Hood: Compliments of Alfred. He insisted I take it along when I said I was going to tail you. Hey Bruce, you gonna eat that slice?

So how did Batman manage to acquire the pizza? Well, it was a bit of a learning process... https://twitter.com/CelticAnarchy/status/1293069121568071681

but eventually the staff of Kane's Pizzeria learned that a growly voiced man calling from a blocked number and asking for his orders to be dead-dropped in a city park not only wasn't a prank, but that whoever was doing it was good for tips in excess of $250 every time.

One time, a delivery driver had to abandon the drop-off because his wife called him right as he loaded up saying she was in labor.

It was a bittersweet moment, because he was about to be a father but also he was about to lose out on the jackpot tip.

But, after the birth of his daughter, a hospital staff member pulled him aside to tell him that a representative of the Wayne Foundation had called on his behalf and would cover the entire cost of the maternity stay pro bono.

And when he, his wife, and his daughter went back to his car to go home, on the driver's seat was an envelope containing $250, marked only by a small bat in the corner.

He immediately knew, but keeps it his little secret.

Batman's gauntlet communicator started beeping. He quickly tapped the button on it.

Batman: Jim?
Jim Gordon: It's Joker.
Batman: What's he done now?
Jim: Well.. he's taken a hostage in the middle of Gotham Square. He's armed with an obviously unloaded water pistol.

Batman: Your men won't move on him?
Jim: Well, you know his history. They know you're better than them at handling him.
Batman: Alright, I'm on it.
Jim: And Batman...
Batman: Yes, Jim?
Jim: He's crying.

Within moments, Batman swoops down on the scene in Gotham Square. He steels himself and puts forth his most intimidating voice.

Batman: Release the hostage!

Almost to Batman's surprise, the Joker releases the hostage with absolutely no resistance.

Instead of his usual cackling, the Joker tosses aside the water pistol and stumbles toward Batman with heaving, broken sobs.

Batman: What's gotten into you?
Joker: It's Harley...
Batman: What about her?
Joker: Batman, they found her dead earlier tonight.

Batman: ...what?...
Joker: It's true! One of my cronies delivered the police report herself.

Batman taps the communicator on his gauntlet: Jim, is this true?
Jim: As far as I can tell, it is.

Joker begins bawling and stumbles toward Batman. Instinctively, Batman puts his hand on Joker's shoulder, although he can't quite bring himself to say "I'm sorry".

Joker: Back when you prevented me from shooting Barbara Gordon, you offered me a chance at rehabilitation.
Batman: I did.
Joker: I said it was far too late for me.
Batman: You did.

Joker: But with Harley gone... I have nothing left to live for. There isn't a reason for me to be... ME, anymore. Can you forgive me? Is there a third chance for me?
Batman: ...There is.

Batman motions for an ambulance on the perimeter to approach.

The EMT inside is young, nervous. He can't have been on the job more than a couple of weeks.

Batman: Don't worry. You're under my protection. Although, I don't think he'll be a problem. Take him to Arkham Psychiatric. Passcode Batman1935.

Joker: Batman?
Batman: Yes?
Joker: Thank you.

Batman closes the door of the ambulance and pounds the side to signal the driver to shove off.

A presence makes him stiff up, although not in response to a threat.

Batman: So what made you fake your death?

Harley: You can tell already?
Batman: Nobody else besides the Joker and Two-Face has snuck up on me like that, and Harvey has no reason to be here.
Harley: Well... It was, eventually I realized that he was only committing crimes to impress me.

Harley: Every time he did something, he would run it by me for approval, and how I reacted would determine how severe his next act was. Eventually I figured that if I wasn't around anymore, he would just... stop. I guess I was right.
Batman: It was an excellent deduction.

Batman: But. You know, if he finds out this was faked, he might regress to the way he was.
Harley: That won't happen.

Harley strode up to Batman and handed him a card. "Charlie Isley, PhD in psychology".

Harley: At your service!

Batman looked at the card, then back up at Harley.

Batman: What will you do now?
Harley: You mean... How will I make up for it?
Batman: Yes.

Harley: Well, I know you don't need any more Robins, but I heard the Batgirl position is opened now that she graduated to Batwoman and struck out on her own.

Despite himself, the corner of Batman's mouth pulled up at this.

Batman tapped a button on his gauntlet and a small piece of paper popped out, with an address printed on it.

Batman: Meet me at this address tomorrow night.

...

And wear something dark.