Mark Renton
Former drug addict Renton stole £16,000 from his friends that came from a drug deal twenty years ago. Since then he’s been living in Amsterdam, gotten married but is inching closer to divorce and has a heart attack while running on a treadmill in a gym. For the first time since betraying his friends, he has returned home.
Daniel “Spud” Murphy
Literally one of the first thing that Renton does upon returning home is save his old friend and fellow drug addict Spud from killing himself. Rather than being thankful, Spud spews venom toward Renton for first ruining his life and now ruining his death. Spud, on the advice of Veronika, starts writing down the funny stories he’s been telling about his youth.
Veronika
Veronika is a Bulgarian immigrant who works as a hooker whose liaisons are filmed in order to blackmail her wealthier clients. She joins up in a scheme with Renton to make a fraudulent application from the EU for £100,000. Both of these criminal activities involve her boyfriend/partner, Simon.
Simon “Sick Boy” Williamson
Simon Williamson was also a part of the gang of drug addicts with whom Renton used to hang out. Back then he was known as “Sick Boy.” He was also betrayed by Renton in the drug deal. Now he films Veronika having sex before approaching them with the evidence to make a deal. He is also involved with Renton and Veronika in the attempt to defraud the EU. The second incident greeting Renton upon his return home is to get beaten badly in a fight with Simon. Sick Boy, like Spud, is still abusing.
Francis Begbie
Begbie also used to be part of the informal group hanging out together along with Renton, Spud and Sick Boy. Unlike them, however, Begbie’s preferred means of self-abuse is alcohol. Unlike the others, however, Begbie is a genuine psychopath with a taste for violence and engaged in much harder criminal activities. As a result of the drug deal which allowed Renton to escape his past, Begbie is less than halfway through his prison sentence when Renton returns. Using equally violent measures against himself, Begbie arranges an escape from the hospital and commits to extracting revenge.
Gail
Gail is Spud’s estranged wife, the loss of whom is partly what inspires his suicide attempt before Renton arrives to save him. As the film story draws to a close, she is looking through a stack of papers. Spud has taken Veronika up on her advice and written them down. The final line of dialogue is Gail telling Spud, “I thought of a title.” The implication is that the book Spud has written will turn out to be Trainspotting.
