Heroin addict Mark Renton stumbles through bad ideas and sobriety attempts with his unreliable friends -- Sick Boy, Begbie, Spud and Tommy. He also has an underage girlfriend, Diane, along for the ride. After cleaning up and moving from Edinburgh to London, Mark finds he can't escape the life he left behind when Begbie shows up at his front door on the lam, and a scheming Sick Boy follows.

After 20 years abroad, Mark Renton returns to Scotland and reunites with his old friends Sick Boy, Spud and Begbie.

Three teenage brothers, gang-member Bobby, troubled mama's boy Alan and self-assured prankster Lex, reside in a downtrodden section of Glasgow, Scotland, circa 1968. But while Bobby and Alan are beginning to experience the power of raging hormones, the story focuses on Lex, who begins a downward spiral after he accidentally shoots the leader of Bobby's gang. Lex's cockiness and immaturity unfortunately prevent him from understanding the effect his subsequent crimes will have on both himself, and on those around him.