A film that shows what makes heroin addictive without glorifying it, Trainspotting was one of the most popular and controversial British films of the 1990s. Exploding with morbid wit, kinetic energy, and fatalistic insight, it jolted critics and audiences regardless of whether or not they actually liked it. A twisting, riff-filled, almost plot-free story, Irvine Welsh's novel was almost unfilmable in its original form. The screen adaptation successfully streamlined Welsh's ungainly material into a slick social commentary that smoothed the book's rough edges without losing its vitriol and insight. Trainspotting is not merely about drug addiction, but about the relationship between wasted youth and the spiritually bankrupt society that has alienated them. Another of the film's great strengths was its ensemble casting of Ewan McGregor, Robert Carlyle, Jonny Lee Miller, and Ewen Bremner. McGregor and Carlyle, in particular, turned in star-making performances as Renton, the film's affable narrator, and Begbie, its resident psychotic drunk. Their work, and that of their co-stars, makes for such compulsively enjoyable viewing that, fittingly enough, you'll have a hard time coming down afterwards.