When Daniel Radcliffe first walks in I can’t believe how terrible he looks: sallow-faced, dark smudges under his eyes, long beard. And so thin. At least a stone lighter than when we met four years ago. And he wasn’t remotely big then. It quickly becomes obvious that he’s starving himself.

He tells me he is subsisting on a daily diet of one chicken breast and a protein bar, boosted by coffee and cigarettes. Radcliffe has been getting into character for his role in Jungle, a film adapted from a true story, where he plays Yossi Ghinsberg, a young adventurer who gets lost in the Bolivian jungle.

He has a few more ‘skinny scenes’ to shoot and then plans to celebrate with a chocolate bar. It’s not the first time he’s gone to extremes for a role. As Harry Potter, for example, he spent 41 hours being filmed under water (in The Goblet of Fire) when he couldn’t swim.