A mentally retarded man named Seymour (John Leguizamo) lives in a world of violence. On the basketball ball court, he is held at razor point and forced to speak perversions. At a rally where his activist mother Mona (Julie Carmen) protests against police brutality, Seymour watches a man bleed to death from a gun shot wound. And his best friend (Michael Rapaport) shows Seymour how to stick up for himself by using a gun. Seymour`s dad, Jack (Cliff Gorman) is the kind of man who brings a flask to the bar. He has a cruel habit of telling Seymour he is a hustler who pretends to be retarded so he doesn`t have to move out of his mother`s house. One morning, Mona is shot and killed in her apartment by Lil` Mafia (Justin Pierce), a neighborhood kid and the son of a prostitute-junkie named Mermaid (Annabella Sciorra). Mona`s ditzy, pot-head girlfriend (Rosie Perez, the director`s wife) joins up with Jack and a cop (Marisa Tomei) to search for Mona`s killer. The poignancy of Mona`s death comes in a flashback when Mona tells Seymour he can`t go outside because inside it`s safe, outside people get shot.