WTF? A sequel to Trainspotting? Ah, but director Danny Boyle, we like to think, is above the usual Hollywood cash grab. It’s been 20 years since Mark (Ewan McGregor) ran off with the £16,000 he and his three mates had stolen, and he’s back in Edinburgh for reasons best left for him to explain. He hooks up, with mixed responses, with Spud (Ewen Bremmer) and Sick Boy (Jonny Lee Miller). And Begbie (Robert Carlyle), menacing as ever, breaks out of prison for the occasion. Though this lacks the original’s youthful zip and snarky humor, it’s disarmingly sadder and wiser, and can stand on its own. (117 min)