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Despite the bleak and depressing nature of the movie, there are still some moments where Arthur Fleck manages to make people genuinely smile.- Arthur entertaining a child in the bus with funny face antics. Except this gets him in trouble with the child's mother.
- The scene where Arthur is sitting in the audience watching Murray Franklin on stage and laughing loud enough for Murray to notice him with the spotlights shown on him. When he tells Murray how much he admires him, Murray calls him down to the stage with the audience being passionate and charmed when Arthur states that he believes his purpose in life was to put smiles on people's faces and doing the best he can to support his mother, with Murray coming forward to embrace him in a hug, stating that he sounds like a man he'd love to have as a son, just wanting to do good for others. It may just be Arthur imagining the entire thing and he probably never really was in the audience, but still, it's very sweet to see, as it shows that Arthur truly did want to fulfill his dreams of changing the world, to make the jaded people of Gotham more happier and being admired by them. Except that never happens and Murray is revealed to have used his clips as a stand-up comedian to mock him.
- Arthur entertains kids in a cancer ward with his clowning. Except that he drops his gun on the floor, resulting in the loss of his job.
- Arthur's on the straight path to villainy, but he finally has an epiphany of sorts in his sad mess of a life.Arthur: Through my whole life, I didn't know if I really existed. But I do, and people are starting to notice.
- The woman that was getting harassed by those three yuppies before they were killed by Arthur is heavily implied to be the woman in the clown mask that Arthur spots in a taxi. What better way to honor a person who potentially saved one's own life?
- Arthur spares Gary’s life while going off the deep end, telling him that he was always nice to him. This gets foreshadowed at the beginning of the scene. While Arthur glares at Randall, he warmly smiles when he sees Gary.
- An earlier scene shows Arthur laughing at a dwarf joke that Randall hurls at Gary, but it's not because he finds the joke funny. Due to his condition, it's more likely that he found the joke hurtful. Notably, he stops laughing as soon as he leaves the changing room, and his face is blank.
- The reason why he was visiting Arthur counts too: while Randall is there because of the gun issue, Gary seems to be genuinely worried about Arthur after hearing that his mother died.
- When Arthur believes he's Thomas Wayne's illegitimate son and goes to Wayne Manor to confront him, what's the first thing he does when he sees young Bruce Wayne? He clowns around and tries to make him smile. Considering the relationship between Jokes and Bats in most continuities, this casts a rather darkly humorous yet heartwarming backdrop over the whole scene.
- While a bit dark as Arthur nearly chokes Alfred when visiting the Wayne Manor, he stops himself and then runs off. Why? Young Bruce Wayne was watching. Even before he went into the villainous path, Arthur couldn't bare to let a kid be affected by trauma like that. But considering what we know about the Joker, well...
- While tailing Thomas Wayne at the theater, Arthur takes a moment to enjoy Charlie Chaplin's antics during the screening of Modern Times. Notable for being one of the rare occasions where Arthur lets out a genuine chuckle, as opposed to the manic scream-cackles caused by his condition, swaying along to the lighthearted music.
- Arthur's therapist confides in him that the city doesn't care about people like him or her. While it's a sad moment, it is implied that she does genuinely care about Arthur, and is upset about not having the resources or time to do more for him.
- Thomas Wayne may be more of a jerk than how he's usually portrayed, but after he confronts Arthur, he warns him not to touch his son again.
- While it's definitely too little, too late, Murray Franklin attempted to reassure Arthur that people aren't as bad as he thinks.
- Murray Franklin makes several genuine attempts to try and understand why Arthur killed the three men on the train (whether it's because he's crazy, to start a movement, a dig at Thomas Wayne), while also trying to reason with him for much longer than he had to. Too bad that, at this point, Arthur is way too far gone to be reasoned with.
- After Arthur forcibly kisses a woman on Murray's show without her consent. Murray Franklin constantly asks if she is okay and tries to comfort her. Which is kinda sweet considering he's usually shown as a jerk.
- After killing Murray Franklin, Arthur is freed from custody when an ambulance crashes into the police cruiser's he's riding in. The clown rioters inside, who apparently recognize their icon, pull him to safety, and when Arthur comes to, he finds himself surrounded by a cheering crowd. In one of the film's most iconic moments, he drags himself to his feet, paints the blood on his face into his trademark rictus, and dances as they roar with approval. Whether it's a hallucination or not, Arthur Fleck, who's been hated, feared and ignored by almost everyone, has been reborn as the Joker, and for one brief shining moment, his loss of identity no longer matters. Everything falls into place in the most savage and bittersweet way possible. Gotham's downtrodden have a hero to call their own, and the Joker, at long last, has an audience who loves him.
- It’s bittersweet, and heavy on the bitter, but seeing Batman’s origins playing out can be interpreted as the movie telling us that even in the darkest of times there’s always hope for the future. And that hope can come from the most unexpected of places. In Gotham’s darkest time, the Batman, its savior, was born.
- Even if Sophie Dumond wasn't the person Arthur Fleck was hallucinating her as, she's still shown to be a sympathetic and understanding person. After he broke into her apartment, she's scared but fully aware how mentally ill Arthur is and politely asks him to leave. He complies without aggression.
