When stage-mad Derek Granger first saw Laurence Olivier as a “quivering sex-mad Veronese” in the 1935 stage production of Romeo And Juliet, the seeds were sown for a lifelong admiration, professional collaboration and family friendship, all of which we heard something about at the Clifton Montpelier Powis Festival. Granger was to become a distinguished theatre and television producer, working with LWT and Granada alongside the invitation to become Olivier’s literary consultant at the new National Theatre.

Granger knew a rather different version of the austere and intimidating actor of my youth: to his friend “Boysie”, Olivier offstage was “cosy, great fun and very companionable”. He liked practical jokes. He was immensely and inclusively generous, hospitable on a democratically Tolstoyan scale. Onstage he was the ultimate perfectionist, achieving character through every nuance of voice, walk, appearance and physique. His own violent physical exertions for theatrical effect caused frequent injuries, requiring long swims back to recovery.

But if Olivier became a star with other people’s words, Granger is a bit of a star with his own. A stream of fascinating anecdotes, delivered in beautiful, old-fashioned English, kept a large audience in St Nicholas Church vastly entertained. Only the clock stopped him, but he – and we – could have gone on all afternoon.

The Prince And The Showgirl, Terence Rattigan’s 1957 film version of his original play, was screened after Derek Granger’s talk. It illustrated the adorable Marilyn Monroe and a rarely droll Olivier, with moments of inspired silliness from both stars.