What Mental Illness Does Arthur Fleck Have In The Joker Movies?

Joker: Folie à Deux delves deeper into the mental state of Arthur Fleck, leaving many wondering what mental illness – if any – the character has. By the time of Joker: Folie à Deux‘s shocking ending, Arthur Fleck’s character is fleshed out even more so than it was in the first film. While Joker 2‘s DC Easter eggs are prevalent, the film continues the trick established by its predecessor by making Joker a more grounded character who is versed in reality.




The primary way this is done is via the exploration of Arthur Fleck’s mental illness, performed admirably by Joaquin Phoenix in Joker: Folie à Deux‘s cast. The first movie also explored Fleck’s mental state, with Joker 2‘s court-based storyline going even further into this. As Arthur’s defendants try to avoid the death penalty that would put an end to Joker 3‘s potential story, a lot of conversations about Arthur’s mental illness are raised, begging the question of which he has.


Arthur Fleck Has A Neurological Disorder Caused By A Brain Injury

Speculation Has Attributed A Specific Disorder To Joker’s Arthur Fleck


Interestingly, neither Joker nor Joker 2 explicitly state what disorder or mental illness Arthur has. He often is shown, more so in the first movie, to suffer from laughing fits regardless of the situation. Arthur even has a card to explain this to those in public, though it is never visible what illness the card states to explain Arthur’s condition.

As such, a lot of speculation regarding this subject has come from outside of the film’s story. As posted on the National Library of Medicine website, it has been widely speculated that Arthur possesses a neurological disorder called pseudobulbar effect in Joker and Joker 2 that results from a brain injury and causes laughing fits. It is worth noting that neurological disorders come from trauma to the brain and are thus different from mental illnesses, which stem from thoughts, feelings, and environmental factors.

Joker 2’s exploration of Arthur’s physical abuse at the hands of his mother supports the idea of him having brain trauma, causing the

pseudobulbar effect.


Arthur Fleck’s Exact Mental Illness Or Illnesses Are Never Confirmed

Joker 2 Delves Deeper Into Other Interpretations Of Arthur’s Mental State

Arthur Fleck smiles with red lipstick on his face and Harley Quinn smokes next to Joker in Joker Folie a Deux
Custom image by Nicolas Ayala

However, as alluded to, this is all speculation. In Joker and Joker 2, it is never confirmed what exactly Arthur’s illnesses, mental or otherwise, are. That said, Joker: Folie à Deux includes some interesting exploration of this. The film centers primarily around Arthur’s trial for the murders he committed in its predecessor. Naturally, he has a defense lawyer. This lawyer, Maryanne, and Arthur’s doctor are trying to convince the jury that Arthur has dissociative identity disorder (DID) and that Joker is an entirely different personality sharing Arthur’s body.

Dent calls another doctor to the stand who insists Arthur does not have DID, and that his actions as Joker are a result of severe anxiety, loneliness, and PTSD…


On the other side of Arthur’s trial is Harvey Dent, the prosecution. Dent calls another doctor to the stand who insists Arthur does not have DID, and that his actions as Joker are a result of severe anxiety, loneliness, and PTSD from his childhood abuse, but that Arthur was consciously doing so rather than another personality. Overall, Joker: Folie à Deux continues the mental health aspect established in the first movie, despite not moving any closer to a concrete confirmation regarding Arthur’s state.