First there was an opportunity... then there was a betrayal. Twenty years have gone by. Much has changed but just as much remains the same. Mark Renton (Ewan McGregor) returns to the only place he can ever call home. They are waiting for him: Spud (Ewen Bremner), Sick Boy (Jonny Lee Miller), and Begbie (Robert Carlyle). Other old friends are waiting too: sorrow, loss, joy, vengeance, hatred, friendship, love, longing, fear, regret, diamorphine, self-destruction and mortal danger, they are all lined up to welcome him, ready to join the dance.