During the 1980s, a failed stand-up comedian is driven insane and turns to a life of crime and chaos in Gotham City while becoming an infamous psychopathic crime figure.

Jojo, a lonely German boy during World War II has his world shaken when he learns that his single mother is hiding a Jewish girl in their home. Influenced by a buffoonish imaginary version of Adolf Hitler, he begins to question his beliefs and confront the conflict between propaganda and his own humanity.