Trainspotting the Musical | Theatre Royal Haymarket | ★☆☆☆☆ I was 13 when Danny Boyle’s Trainspotting adaptation was released – I’d never seen anything like it and it became a seminal text of my teenage years. Two decades later, I luxuriated in the condensed hit of nostalgia of the 2017 sequel. I’ve read the books: not just the original – a stone-cold classic – but the various follow-ups and spin-offs, even after the quality became… patchy. The…