Joker: Folie à Deux follows the story of two individuals, Arthur Fleck and Maria Martinez, who both struggle with mental illness in a society that fails to support them. Arthur, a failed comedian, becomes the infamous Joker as he descends into madness and chaos, while Maria, a struggling single mother, finds solace in her art but battles her inner demons.
As Arthur's violent acts inspire copycat crimes, Maria finds herself caught in the crossfire and must make a choice between succumbing to her own darkness or finding strength in her struggles. Their paths eventually collide, leading to a dangerous game of cat and mouse that tests the limits of their sanity.
Together, Arthur and Maria explore the concept of "Folie à Deux," a shared psychosis between two people, as they navigate their turbulent journey towards self-discovery and redemption in a world that has rejected them. In the end, they must confront their inner demons and face the consequences of their actions in a chilling and thought-provoking tale that challenges the audience to question the thin line between madness and sanity.