"Retirement! What does that mean?" Ian McKellen is scandalised by the suggestion that, at 77, the day may soon come when he takes his last bow on stage.

“Retirement from theatre would mean retirement from life. It doesn’t appeal to me. A few years ago, I decided to take six months off each year and see what happened – and what happened was, I got intensely bored. So I went back.”

It’s the kind of passion that explains a glittering career such as McKellen’s. Six Laurence Olivier Awards, one Tony, a Golden Globe, as well as two Oscars, in roles spanning Shakespeare and Beckett to Tolkien, where he made a legion of younger fans as Gandalf.

He’s soon to be back on the British boards in a revival of Harold Pinter’s No Man’s Land. And it’s clear that the theatre remains his raison d’être. Reminiscences about old producers such as Binky Beaumont trip off his tongue far easier than answers to more personal topics, where McKellen becomes instantly more distant.