1978年10月，性手枪乐团贝斯手席德的女友南西被人发现陈尸于却尔西旅店100号房的浴室，纽约警察未详加调查，将同处一室却早已嗑挂的席德冠上谋杀罪名；席德在隔年二月猝死，南西之死的真相也成为千古悬案。导演访问了近两百名相关人士，试图抽丝剥茧还原出真相。究竟是爱你爱到杀死你，或者席德只是代罪羔羊，凶手另有其人？看完电影，由你决定。

On October 12th, 1978, New York Police discovered the lifeless body of a young woman, slumped under the bathroom sink in a hotel room. She was Nancy Spungen, an ex-prostitute, sometimes stripper, heroin addict, and girlfriend of Sex Pistols' bassist Sid Vicious.