Friendship
Continuing from the first movie, the main theme of the movie is the return of friendship. While the different characters are misfits in most ways and a few betrayals happen on the way, their friendship mostly lasts to the end. The relationship between Mark Renton and Simon "Sick Boy" Williamson is the most outstanding example of this. Sick Boy forgives Renton pretty fast about the betrayal 20 years earlier and Renton tries to help them in getting their life back together. If a movie like this has a moral, the strength of friendship could be considered one of them.
Drug Abuse
Similarly to the original movie, the theme of drug abuse is strong within the movie. The main character, who stole his friends money and became semi successful managed to break the curse and become clean. His old friends who hit hard times stayed in their self destructive bubble. Throughout the movie drugs are a haven characters return to when they feel like the world is getting too much. However, the movie focusses heavily on the negative effects of drugs. Veronika and Sick Boy's relationship is heavily impacted by drugs, as is her friendship with Spud. Renton's return to Edinburgh starts out as a cleansing for all his friends, as a new positive energy has entered their lives. However, the setbacks of the movie do not allow them to become fully clean.
Crime
Another recurring theme from the first movie is crime. Interestingly, this is presented through two different lenses. One the one hand the movie discusses the violent crimes of Begbie in a very negative light that is threatening to the protagonists. On the other hand, the fraudulent acquisition of the 100.000 pounds is seen less problematic. The movie spins an intricate web of what is a crime and what is not and lets the protagonists decide this for themselves. This form of judgement that is separate from an institutionalized system is a recurring concept throughout the movie. However, their interpretation of right and wrong haunts them when they get dragged to court.
Revenge
From the very start, the movie has the dichotomy of reconciliation and revenge as the most prominent themes. Mark returns to Edinburgh to right his old wrongs, while his old friends are out for revenge. In the beginning, even after having received the money back from Mark, Sick Boy swears to enact some form of revenge on Mark, which never really happens. The other, more disturbing form of revenge is seen through the character of Begbie, who is driven by a rage to enact revenge on those that got him into prison, in his perspective. Even when he learns that some of his ways are wrong and tries to reconcile with his family, his desire for revenge ultimately ends him up in prison again.
Family
One theme that is evidently strong in the movie is the concept of family. In the beginning of the movie all characters have a broken family life. Mark is estranged from his father, Spud has pretty much abandoned his wife and son, Begbie is a horrible human to his son and even Veronika has left her son in Bulgaria. The characters go different ways to mend the broken bonds, sometimes having to learn the hard way that it was their actions that broke the relationship in the first place. By the end of the movie, most characters had at least some form of reconciliation with their loved ones, including the criminal Begbie.
