Clown (Symbol)
Clown imagery surfaces at many different points throughout the film. The first shot of the film is Arthur applying clown makeup in the mirror, preparing for his day job as a hired clown. Then later, when he commits his first murder, he has just gotten off a job and is made up as a clown. This inspires him to adopt the image of a clown as his persona when he becomes Joker. Then, he goes on Murray Franklin's show in a full clown costume, with dyed hair and whacky makeup. The image of Arthur as the clown symbolizes his marginality from society, the fact that he is a freak and a pariah. He is a clown who has been pushed to his limits and now has a completely demented sense of humor that hinges on violence. As a trope, the clown or the fool symbolizes someone who exists outside of society and subverts it to show the masses the truth. Arthur is an unhinged and malevolent version of this trope.
Additionally, after Arthur murders the men on the subway, people take up the image of the "clown" as a symbol of a class uprising in Gotham. Members of the resistance sport clown masks and begin to riot in the streets. Here, the "clown" becomes a symbol of the lower classes becoming impatient and rising up against Gotham's elite, wearing their marginality as a perversely proud symbol of their anger and rebellion.
Arthur's First Murder (Symbol)
Arthur's first murder, of the three businessmen who work for Wayne Enterprises, is primarily an act of self-defense against their violent beatings. Because he has a gun on him and he struggles with mental illness, he uses it against the men, and then becomes so incensed that he kills the third one in cold blood. It is a random and chaotic act, yet the citizens of Gotham interpret it as a symbol of a class uprising. While Arthur certainly has a great deal of malice towards the men on the subway, which has much to do with their class entitlement, unchecked sense of privilege, and arrogance, his act is not a calculated political one. This symbolic act, the murder, sets off a whole revolution in the city, even though it is without intention.
Gun (Symbol)
After hearing about how Arthur got beat up by the gang of boys, Arthur's coworker Randall gives him a gun for protection. Given the fact that they are not allowed to have guns in their job and Arthur has pretty severe mental illness, this is an unwise gift. When Arthur gets his hand on the gun, even though he knows he should not have it, his self-esteem improves. He begins to stand up for himself, and eventually, he uses the gun to kill people. The gun is a symbol of empowerment for someone who has barely any power in the world. It becomes a symbol of confidence, power, and vigilantist violence, the method by which Arthur becomes an infamous Gotham villain.
Arthur Dancing (Motif)
Arthur dances at several points in the film, first after killing the three men on the subway, then down the steps outside his apartment building after killing Randall, then as he enters the stage on Murray Franklin's show, and then at the very end, after he's killed the social worker at Arkham's. Arthur's dancing represents his descent into madness and his transformation into "Joker." In situations that ought to make him feel emotional, scared, or regretful, he is filled with a maniacal joy from within, a bodily response to his own pathos that turns tragedy into comedy, pain into a perverse and terrifying pleasure.
Murray Franklin and Thomas Wayne (Symbols)
Arthur has no father, and must care for his ailing mother in their squalid apartment. In many ways, he is searching for a paternal role model to encourage him in life. The two people who symbolize paternal care for Arthur are Murray Franklin, a talk-show host who represents the comedic success that Arthur so longs for, and Thomas Wayne, the wealthiest man in Gotham, whom his mother insists is Arthur's illegitimate father. The two men, from Arthur's perspective, come to represent father figures, people who could help Arthur to blossom into a well-adjusted and happier person. However, they both let him down in different ways, and he ends up more disappointed than ever. In this way, they can be thought to symbolize the way that society itself and those in power are paternal figures for those who are less fortunate, charged with providing for the more vulnerable in society. In Joker, they prove to be disappointing dads, falling short and failing the citizens who need them most.
