If it’s just a bad day that separates us from madness Joker was right. This phrase doesn’t appear in the last film directed by Todd Phillips. But Joker, as himself, carries all the narrative references of his comic book’s universe: he was born in 1940 coupled with Batman, but then, like any character, he began to live his own life, even individually in subsequent films, books, comics and not only.
It was Oreste del Buono (with Rivista Linus), a friend of Carmelo Bene, who founded the studies on comics in Italy: the comic is recognized as a medium to express important ideas as novels but through different media. Narrative universe of characters is formed, as in the novels (for example, The three Musketeers, all the characters of Tabucchi) but in the comics they already have features, easier to transpose on the screen. In fact, in 1941 in America the first movies based on comics were born: The Adventures of Captain Marvel and then the timeless Superman (’43).
This allows us to convey meanings that go beyond the single work as happened in the Greek myths, not by chance these are also called heroes. These try to explain the origin of something or human behavior. A bit as if the characters had replaced the Gods in our agnostic age. And in the Todd Phillips movie, as in the comic strip, where the people of Gotham acclaim these superman Gods, this transpires. Even in everyday reality, the popular heroes Marvel and Dc have created violent emulation phenomena for which the movie viewing room has been put on alert in America.
Here is the film in blu ray: https://amzn.to/2Nh582N
Actually it’s not the only one to create a crazy and lonely character who paradoxically cannot help but laugh. Victor Hugo had created such a character that he had a facial paresis in The Man who laughs.
Another book instead, whose title I don’t remember (I think a South American author, perhaps a novel by Jorge Amado), presents a clown who couldn’t be sad because a surgery had left his mouth in a grimace of a smile.
A book by Austrian Heirich Boll portrays a lone clown, who has lost all value, and who lashes the company: https://amzn.to/2WKNkA0 [opinions of a clown].