Bruce Robinson is ramming a huge log into the grate of his ancient fireplace in mud-clogged Herefordshire. He’s 77 and the film for which he is famous, Withnail and I, is about to open as a play. Isn’t it curious it hasn’t happened before, given that the comedy is about two thirsty, unemployed actors and is a sort of love-hate letter to the theatre?

‘I was living on 30 bob a week – I could either afford fish and chips or ten gold leaf’

‘I wasn’t fond of the idea of staging it,’ says Robinson, who wrote and directed the 1987 film...