Be prepared for a love-hate relationship. Be warned that there are haunting after-effects. They are a sordid mess, living in a wretched personality sinkhole of apathy and cynicism. They are portrayed in John Hodge's witty and wise screenplay as neither victims of economic circumstances nor luckless saps of social situations. Their amoral journeys, Renton's included, begin and end, evolve and revolve, around their heroin drug of no choice.
Silly farce gives way to face-covering horror.
The mix is magical and mesmerizing, and ultimately unnerving.