I recently heard Sir Michael Gambon weep. It was around 9.41am on Good Friday, and I was listening to the first in the new series of Radio 4's The Reunion. Presenter Sue Macgregor had assembled some of the privileged few who'd been present for the founding of the National Theatre, under the leadership of Sir Laurence Olivier, in October 1963.

She began by telling us that tickets for the first production – of Hamlet, at the Old Vic – went on sale for the princely (boom boom) sum of three shillings; that's 15 pence today. Forty minutes and 30 seconds of fascinating reminiscences later, Gambon, one of her guests, began to cry at the memory of his mentor, Sir Larry.

I have some friends who are actors. Not famous actors, mind you, but they try their best. Thinking they'd be interested by the programme, I went about recommending it to them. They wearily acknowledged my mentions of Macgregor's other interviewees: the acclaimed director Bill Gaskill; Dame Maggie Smith; Sir Derek Jacobi; Dame Joan Plowright (yes, Mrs Olivier lives on – who knew?). But to this roll call of theatrical giants, my actor pals just nodded soberly, as if trying to recall the plot of Gosford Park.

It was only when I finished my description of the programme with the word "Gambon" that their eyes lit up. Gambon. It's a satisfying surname to say out loud: "Gam-bon". Full of hard consonants; muscular yet refined, like a shoulder of ham imported from the continent. "Gambon!" said the struggling thesps, "He's brilliant."

Well, okay, he is sort of brilliant. But is he really so much more brilliant than everyone else? I mean, Derek Jacobi – he was Cadfael! What is it about Gambon that people so adore? He's a great actor, but in the way that Michael Caine's a great actor, not in the way that, say, Daniel Day-Lewis is a great actor. Whether he's playing Falstaff or Philip Marlow, that wry, rogueish essence of Gambon remains.

Somehow, however, he appeals to every constituency. Here's a man who can get away with blubbing at the recollection of Olivier's greatest performances, yet still have a corner named after him on the Top Gear test track. Ralph Richardson, one of the 20th century's leading Shakespeareans, called him "The Great Gambon"; Cubby Broccoli briefly hoped he might replace George Lazenby as Bond.

To cultural sophisticates of 30-plus years of age, he's the evil git of Greenaway's The Cook, The Thief, His Wife and Her Lover; to everyone else aged three to 93, he's Professor Dumbledore. He's one of those older gents for whom young women harbour vaguely inappropriate crushes, like Jon Snow; and young men see him as the rascal they wouldn't mind growing into.

Maybe it's his Irish roots; Gambon seems like he ought to be raising hell with Richard Harris and Peter O'Toole in the back room of some smoky Dublin pub. And he has a worthy O'Toole anecdote: the elder actor played Hamlet in '63, Gambon a supporting role. One night, he told Macgregor, he was summoned to the star's dressing room. "He said, 'Are you the one who pulls me out of the grave in the Yorick scene?' And I said yes. And he said, 'Don't pull so bloody hard. You're hurting me.'"

Another great Good Friday theatrical anecdote came, again, courtesy of Radio 4. Sir Alan Ayckbourn, whose work was being celebrated by the station in honour of his 70th birthday, was talking to Mark Lawson, and recalled a funny episode in a pub with Harold Pinter, CBE (who gave Gambon some of his best stage roles). I shan't trouble you with it here, as Sir Alan tells it much better, but it's on iPlayer, about 17 minutes into a lengthy interview from Front Row's 10 April edition, which the BBC website assures me will be available for your listening pleasure until 2099. What a shame the same can't be said for Olivier, for Ayckbourn, or for young Gambon.

Access unlimited streaming of movies and TV shows with Amazon Prime Video Sign up now for a 30-day free trial

Sign up

***

They're still milking that T-Mobile ad, I see. You know, the one where everyone starts dancing "spontaneously" in Liverpool Street Station. Flashmobbing was cool for about five minutes, five years ago. Its coolness was derived from at least two things that the commercial explicitly lacks. First, spontaneity of a sort, or at least not the thousands of man hours of choreography practice in a dance studio somewhere that the ad evidently entailed. And second, the spirit of so-called "culture jamming". Asking the rail authorities for permission, and then using the results as TV spots for a mobile phone company, doesn't count.