It wasn't until the two of them almost entered Canada that Arthur realized Bruce was actually looking for him to perform in the comedy show at the opening ceremony of the music festival.
At that time, Arthur had not taken the promise seriously at all, because it was obvious that in no universe would Arthur be a comedy master. Why would Bruce Wayne bother to invite someone as unknown as him? Yet he actually did.
What was embarrassing was that Arthur couldn't return to the psychiatric hospital now, because if it was just about publicly shooting a comedian, there was still a chance for lifetime Healing, but attacking the Federal Reserve System was essentially the same as shooting oneself in the back eight times.
Arthur could only be thankful that he wasn't Thomas' illegitimate son; he couldn't imagine how that little tyke he saw at Wayne Manor 20 years later had turned out so insane.
But Arthur knew he had to go this time whether he liked it or not, otherwise the Federal Bureau of Investigation would chase him to the ends of the earth, and without Bruce's help, he wouldn't stand a chance of escaping on his own.
So, he followed Bruce to the Battleworld's transfer station. However, it was there that Bruce suggested he see a psychologist. Naturally, Arthur refused.
Moreover, it was then that Bruce introduced his college major and academic history to Arthur, and that was when Arthur learned that Bruce almost didn't graduate.
To persuade this crazy teenager, Arthur had no choice but to reveal some of his own personal history; he didn't really expect Bruce to understand, because people of that age seem to think everything can be saved.
Unexpectedly, Bruce didn't ask any further questions. Arthur thought the matter would end there—not because he was unguarded, but because in the film era Arthur came from, Bruce Wayne was just a child and had nothing to do with Batman.
Even though he had seen Batman before during his time in Battleworld, it was all hearsay without personal experience; one cannot fathom what Batman really is.
Then Arthur was knocked out by Bruce with a syringe, and by the time he woke up, the surgery was already finished.
It has been mentioned before that Arthur has been mentally ill since his first appearance—his mental illness was not hereditary, but due to the abuse suffered at the hands of his foster mother and her lover, which caused brain damage.
His condition that made him burst into loud laughter was not only because his foster mother didn't like to hear young Arthur cry, forcing him to keep laughing, but also due to brain damage that caused his emotional mapping system to be disordered, and his facial muscles to be out of control.
Arthur didn't know what Bruce had done, but anyway, he saw a perfectly healthy brain on his CT scan after the Healing, and he found it hard to describe his emotions.
Of course, he felt a bit of an angry embarrassment, because among all the Jokers, Arthur could be said to be the one closest to a normal person—he had his own spectrum of emotions and didn't engage in antisocial acts just because he was born insane. He was more like an oppressed common man, so naturally, he got angry.
But could Bruce ever fail to understand the Joker? He immediately told Arthur that the moment he first saw him, he sensed Arthur would be a great comedian in the future, which is why he invited him to perform at the music festival.
After arriving in this cosmos and before bailing out Arthur, Bruce had even gone out of his way to watch Arthur's television performances. He discovered that Arthur's topics, ideas, and performance style were very good, but the uncontrollable twitching and laughter were the only things affecting his performance.
Many people were annoyed by those canned laugh tracks that seemed to appear at any moment. People didn't buy tickets to comedy shows to see comedians laugh uncontrollably at points that weren't funny—appearing so desperate that they could only force a laugh on stage.
This was in fact the reason why Arthur's performances were unpopular—his laughing condition was like adding too many unwanted canned laughs to ever comedy show. You can't say it wasn't a good meal, but with so many rat droppings mixed in, nobody would want to eat it.
By Healing Arthur's brain, Bruce, to some extent, at least ensured that Arthur wouldn't burst into uncontrollable laughter, meaning Arthur now had a chance to become a true master of comedy.
Arthur was a bit angry, but not much; he quickly turned around to start writing his script.
In the movie, the Joker might seem ferocious, but if one examines the details of his few murder cases, they can qualify as revenge for a grudge—even Franklin, who was the least related to him, mocked Arthur on television, making him a laughingstock. Therefore, Arthur's portrayal was closer to a tragic common man and not a born lunatic with cruel and crazy thoughts.
A born psychopath kills without regard for their own age or the victim's identity. If it were any other cosmos' Joker, the moment he could wield a knife, both his foster mother and her lover would be in big trouble, regardless of whether they abused him or not.
And precisely because Arthur was more like an ordinary person, he understood the joys and sorrows of ordinary people better, so he was more suited to be a comedy master, not a Joker who thought only about amusing another mentally ill person like Batman every day.
On stage, Arthur detailed his life story with a humor that was incredibly engaging; first, he threw out a sensational punchline to capture everyone's attention, and then, with a narrative in reverse order, he vividly described the tense and exciting preparation to confront Thomas.
He then described Wayne Manor as an underground fortress, with Thomas likened to an Evil Dragon lurking at its deepest point. The hero, after extraordinary struggles, finally faced him, only to be swatted on the nose by the dragon.
When they heard this, many were still indignant, feeling the need to stand up for Joker, thinking Thomas was heartlessly rich. However, Arthur's tone changed as he said he went to Arkham Psychiatric Hospital to investigate and discovered his adoptive mother was indeed a fucking lunatic stalker. Realizing he didn't take that punch undeservedly, everyone laughed it off again.
Arthur stood straight in the center of the stage, one hand still in his pocket, but this time he leaned his upper body back, tucking in his chin nearly enough to give himself a double chin.
"The most interesting part of this story is that, in addition to confirming I'm certainly not Thomas's seed, I also figured out why I can't stop laughing uncontrollably. Guess what it is?"
The audience murmured among themselves, believing it must be because his crazy mother was too busy stalking Thomas to care for little Arthur, leading to a head injury. Others speculated it might be a hereditary mental illness.
"Don't know if you've had this kind of experience," Arthur started pacing with his head down, hands still in his pockets, eyes staring at the ground as he said, "Your mother tells you to do this and not that, this is right and that's wrong."
"Usually, this is very helpful because, most of the time, telling you not to put your hand into a hot pot is genuinely for your good. Those who completely praise and encourage their kids, their children certainly don't swim in hot pots, which proves they are not encouraging about that."
"But little kids are not so simple creatures. Those cheering must share my thoughts; they are the most dreadful bastards in the world, you wouldn't believe the genius ideas they come up with, inventing new ways to die that no one has ever seen before."
"Then you take further action. At first, you shout at them, and then maybe hit them a couple of times. Yes, I know it's illegal, but can you sail them out to international waters on a yacht to beat them up? Who do you think you are? Bruce Wayne?"
Arthur, mimicking Bruce's accent and intonation, said, "Listen! My dear son Little Bruce! What have I got in my hand? The United Nations Convention on the Law of the Sea!"
"...But we're Americans, so this is just a piece of paper! We only recognize three miles of territorial sea! That means in 2.98 nautical miles you're getting a beating!"
Then he laughed and said, "Yes, my friend, that's how law-abiding he is, rich people always have a way, don't they?"
Another wave of laughter came from the audience.
"To stop them from getting killed, it's no problem to give their backsides a hard couple of whacks. Then you'll quickly realize how effective that is."
"Threats and intimidation are always the simplest way to control someone. Too easy, isn't it? You're nearly a 200-pound adult, a little louder footsteps can scare the daylights out of those kids."
"So one irritation in your life is permanently solved, things gradually become simpler, and it shifts from them not being allowed to do this so you threaten them, to you not wanting them to do this so you threaten them. The choice is always yours."
Arthur stopped pacing, faced the audience and said, "This sounds like I'm preaching, teaching you how to be good parents, but I have to say, my foster mother made many bad choices for me."
"Throughout my childhood, she thought my crying sounded awful, so she chose to make me laugh, it had to be laughter, and thus I kept laughing, uncontrollably."
The audience quieted down, realizing that this was not a comedian elevating his material because the heaviness and sadness were too real. One didn't need a keen empathy to tell it was not a joke.
"So, we come back to the original point," Arthur switched hands with the microphone and said, "I was diagnosed with a mental disorder, then I went to see a lousy psychiatrist, who impatiently looked at me as if I were taking an exam."
"Believe me, I paid an unimaginable price for my uncontrollable laughter, turning me into what I am today. Decisions made on my behalf in my childhood, kept on making decisions for me my whole life."
Arthur spread his hands and said, "I was misunderstood, got fired, the clinic I frequently visited shut down. Decisions the society made for me ultimately made me make my decisions."
"So, if ever you realize that some of your actions are making decisions for someone else, always assume the worst."
Arthur dragged out the sound, looking at Bruce.
"Then, when you find your kind gestures have led some people to make good decisions, you'll be genuinely surprised, and you'll laugh heartily out of pure joy—go ahead and laugh."
Bruce and Arthur laughed together.