湿冷无望的哥谭市，卑微的亚瑟·弗兰克（华金·菲尼克斯 Joaquin Phoenix 饰）依靠扮演小丑赚取营生。与之相依为命的母亲患有精神疾病，而亚瑟深记母亲的教诲，无论遭受怎样的挫折都笑对人生，却因此让自己背负着莫大的压力，濒临崩溃。他梦想成为一名脱口秀演员，怎奈生活一次次将失望狠狠地砸在他的头上。不仅如此，他因意外丢掉了工作，偶然瞥见母亲的秘密，又使他心中燃起对那个与之地位悬殊却从未谋面的父亲的殷切渴望。命运习惯了事与愿违，空荡荡的地铁内，悲伤的小丑在无法自已的癫狂笑声中大开杀戒…… 本片荣获第76届威尼斯电影节金狮奖。
Based on real events, from the life of Andrea Casamento. Andrea's life, a middle-class woman, changes drastically when her 18 year-old son ends up in jail falsely accused for a misdemeanor he did not commit. Now she must dedicate his days to freeing him from jail. To release him, she has to face the bureaucracy of the judicial system, prisoner abuse, but above all her own prejudices, values and beliefs. She will realize of this powerful change when she can't help falling in love with a convict.
