Shirley Clarke's savagely realistic yet poetic study of Harlem youth and slum life was based on a novel and a play, but as a Newsweek critic noted, “its structure as fiction is of rather minor importance.... The power of the film is in Miss Clarke's vision of Harlem, and the manner in which she uses that vision is the purest kind of moviemaking. This is...a work of art informed by knowing compassion.... The authenticity of the dialogue was the great virtue of the Warren Miller novel. (Screenwriters) Clarke and (Carl) Lee (son of actor Canada Lee) have honed it even finer, and its effect in a film is vastly more powerful.”
Certainly much of the film's realistic semi-documentary style is due to the location shooting (the film has the distinction of being the first feature made with a handheld 35mm camera) and the casting of nonprofessional adolescent actors who were really street gang kids. Improvisation was used for the casting and carried over to some of the actual shooting. Regarded as one of the central works of the New York School of filmmaking, The Cool World remains a classic of social realist drama, with a raw vitality and artistic strength that still holds up today.