Irvine Welsh with the same name in 2013. "Glue" (2001) was a return to the locations, themes and episodic form of "Trainspotting", telling the stories of four characters spanning several decades in their lives and the bonds that held them together. Having revisited some of them in passing in "Glue", Welsh brought most of the "Trainspotting" characters back for a sequel, "Porno", in 2002. In this book Welsh explores the impact of pornography on the individuals involved in producing it, as well as society as a whole, and the impact of ageing and maturity in individuals against their will. The book is
Candy: A Novel of Love and Addiction and shortly afterward Casper is caught making heroin. His employer sends him to rehab but Casper leaves, knowing that action marks the end of his career. Casper then gets antidepressants and alcohol, goes to his lab, cooks one last batch, and commits suicide. The narrator goes into rehab and sobers up. He sees Candy the first chance he is allowed to, and she tells him she knows they have to end. They have to stay apart to be clean. "Candy" is an intense, and at times taxing, exploration of the heroin addiction shared by a young couple deeply in love.