In January 1978, on their tour of the United States, the punk rock band Sex Pistols venture outside after his victory in England. Temperamental bassist Sid Vicious is coerced by his own bandmates and their manager to traveling without his girlfriend, Nancy Spungen, that will meet with him following a traumatic occasion only in New York. When the band breaks up and Sid begins his solo career in a city, the couple that is turbulent falls a journey with no return, into the depths of co-dependency and drug dependence.