T2: Trainspotting review: "Wiser, sadder, but very much alive and kicking"

On paper it looks like a scam. The sort of take-the-money-and-run job that Renton (Ewan McGregor) pulled before striding off into the freeze-framed future at the end of Danny Boyle’s 1996 era-defining masterpiece.

Get the gang – director Boyle, novelist Irvine Welsh, under-sung screenwriter John Hodge, producer Andrew MacDonald and a cast now more used to Hollywood than Holyrood – back together; loosely adapt another of Irvine Welsh’s scabrous junk epics (this time, Porno), and retire on the attendant millions to watch “mind-numbing, spirit-crushing game shows, stuffing fucking junk food into their mouths”. Or maybe not.

For 20 years, T2 was the elephant in the room, the madman laughing in the corner; the gang perhaps mindful of Sick Boy’s dictum: “You’ve got it, and then you lose it, and it’s gone forever.” But Boyle, for one, has never lost it, and every frame of this film means something to him, and those who were there the first time. Dizzyingly meta, maddeningly broad, then oddly moving, T2 takes some getting your head round, even for the faithful. Indeed, new viewers may wonder what’s been slipped in their drinks.

It begins, of course, with Renton’s sprinting feet. But they’re pounding a treadmill, rather than the Princes Street tarmac, and he can’t outrun the treachery of his past. A health scare – and worse – drags him back home to a Leith of steep decline and slow regeneration.

Here, Sick Boy (Jonny Lee Miller) pimps out his girlfriend Veronika (Anjela Nedyalkova) for blackmail cash; Francis “Franco” Begbie (Robert Carlyle) is taking the messy route out of Saughton Prison; and Spud (Ewen Bremner) is still a junkie with the soul of a poet.

“You’re a tourist in your own youth,” Sick Boy tells Renton, after a much-deserved beating. “What other moments will you be revisiting?” As Renton, Sick Boy and Veronika cook up a new get-rich-quick scheme, the short answer is, practically all of them.

Some are glorious – Spud freefalling into his old friend’s arms. Some disappoint – the ‘Choose Life’ speech needs no dissection. Some – such as when one character quotes Welsh’s original novel and another acts it out – are so postmodern, they pull you, thrillingly, down the wormhole to Malkovich-land.

Once more, Boyle’s direction is the star here. Busy with verbs, spiky with life, the film fizzes along to a fantastic soundtrack of new friends (Young Fathers) and remixed favourites (‘Born Slippy’). But it’s also slightly diffuse: without Renton’s acid voiceover, the narrative loses that monomaniacal focus, swapping the purity of the original high for a cocktail of different uppers and downers.

With Renton at the centre, everyone else was a (brilliantly realised) bit-part player in his story – the way we all feel when we’re young. With all four leads jostling for that centre, Renton becomes a blank, a silhouette, the everyman he always threatened to be.

However, when he’s singing with Sick Boy (no really) and sprinting with Spud – or from Begbie – the film crackles with the old black magic. And of its many surprises, it saves the best for last. The neon-drenched final reckoning is heart-stopping; the final shot, simply heart-melting.

Trainspotting, you see, was never about the drugs, or the money. It was about youth, about escape. Twenty years on, with middle age encroaching and all hopes of escape long evaporated, T2 isn’t about the drugs, or the money either. It’s about chasing the old highs, realising you can’t reach them and then, if you’re lucky, finding new ones.