Rome. Nina is an aerobics teacher; the few people she goes around with are usually the wrong kind. Along with her immature, drug-addict boyfriend and her middle-aged friend, a former photographer who is always too cynical and too high, she finds herself involved in a feud between a gang of criminals from southern Italy and a gang of Africans who are trying to take over the heroin market. In the meantime, the three friends are suddenly accused of a double homicide which is being investigated by two police detectives.