(there will be spoilers aplenty here, so if you don't want to read about plot points and overall arcs from the sequel to Trainspotting, you probably don't want to read any further. I guess if you haven't read Gateway and you're planning on doing so, you might want to put a pin in this for later.)
My initial thought after seeing T2: Trainspotting was just how much it reminded me of Frederik Pohl's Gateway. Feel free to scratch you head a moment. Let me explain: In Pohl's book, the protagonist is in a spaceship approaching a black hole. The "hero" and his handful of shipmates come up with a plan that might allow them to escape. Instead, perhaps by intent or maybe by accident, screws up the plan, allowing himself to escape while dooming his shipmates to eternal falling into darkness.
You can see how that rhymes with the ending of the first Trainspotting. Renton betrayed his mates and, as the film ends to the tune of Underworld's Born Slippy, he recites a litany of ways he's going to turn over anew leaf and live his old life behind. It's a naive and cynical recitation. He's mocking "you" when he says he's going to be "just like you."
Twenty years go by, and Renton returns home. His abandoned mates are still slowly falling towards oblivion: Begbie's in prison, Spud's back quit heroin and then relapsed and trying to kill himself, and Sick Boy, now calling himself Simon, is running a dingy pub when he's not running blackmail scams and scheming to open a brothel with his perhaps-girlfriend Veronika. No one is particularly happy to see Renton return.
So why did Renton come back? He had a respectable life in Holland with a wife and a steady job as an accountant. At first, his return seems strangely pointless, just an excuse to get the movie in motion. However, it's revealed that Renton's escape was a failure. His wife is leaving him, his company's about to fire him, and he's got nothing. He fucked over his friends to get out, he blew it, and now he's tumbling back in to his old life.
The first film isn't just the jumping off point for the sequel; it's an anchor that keeps tugging at every attempt to break away from its gravity. It's a fascinating way to make a sequel. The first film haunts every shot, and the music echoes the legendary soundtrack of the original. There are messages, subtle and otherwise, all through the film warning of the futility of trying to recapture the past and obviously, those warning could apply to both the making of the film and the viewing of it.
The performances are terrific, particularly those of Ewan McGregor and Jonny Lee Miller as Renton and Simon. Renton's boyish charm is intact, but it's a good deal less charming. Simon's intensity is riveting and their relationship is what carries the movie. They love each other, but there's no trust and they can't get over the past. Veronika, who has been wrongly called an example of the "hooker with a heart of gold" trope, is just removed enough and observant enough to see how things are going and plan accordingly.
Begbie and Spud are more peripheral, providing menace and comedic pathos respectively. They're good, but they're not really central to what the movie is about. Ewen Bremmer as Spud is particularly good and you're left with the sense that he might just have a chance at a brighter, or less dim, future. A few of the other characters from the original return: Mikey Forrester, Rents' father, and, most poignantly, Diane. She's only got one short scene, but it's memorable. She was never really on the same trajectory as the guys, and now she's in an entirely different universe. She offers some good advance that Renton obviously won't take.
The key scene, for me at least, was a dinner conversation between Veronika and Renton where she asks him what "Choose life" is all about. Renton launches into another monologue, similar in form to the one from the first film, but wholly different in content and meaning. It's now the cautionary tale of the damned who has, in fact, attempted to chose life, and every word he speaks is now bitter experience instead of a glib, mocking recitation of other people's values. Even though you knew this scene had to happen, it still works and it's devastating.
The plot felt more like an excuse to explore aging, betrayal, attempting to recapture the past, and failure than to tell a story, but those are some pretty good excuses. There's some incredible camerawork that exhumes and expands upon the first film. My only gripe, technically, was that the bombastic music wasn't as on the nose as the first time around. Don't get me wrong, I love me some Wolf Alice; it just didn't feel as essential to the film as that razor cut from "Temptation" to "Atomic" in the club scene the first time around.
Which is a long way of saying, it's a really odd experience watching T2: Trainspotting. At times, it feels like it's pointing a finger at the audience, chastising them for wanting to relive the thrill of the first film. It's a joyless affair for all its energy. It's shot inventively and, like I said, the performances are terrific and it leaves you with a lot to chew on. In some ways, this was a legitimately better film than Trainspotting, but I didn't enjoy it as much and I doubt I'll revisit it as often, if that makes any sense.