In a career that now spans an astonishing four and a half decades, McCowen has been finding parallels with consistent discernment and accuracy. He returns to Shakespeare after a lengthy absence and to Stratford after fully 30 years; he last played at the Memorial Theatre as Lear's Fool in the Peter Brook production that burns vivid in the memories of those of us fortunate enough to have seen it.
Contemplating how to tackle Prospero, he recalled the South Bank Show profile of David Lean making his movie of Forster's A Passage to India. 'You had this very neat, very aristocratic, very autocratic little man of such temperament. And when the temperament broke out it was so scary and impressive. There was such stubbornness in his film-making. I never met him or worked with him but I heard about the horrendous time they had on Ryan's Daughter where he had tried to control the elements and they hung around in Ireland for months while he tried to get the storm he wanted. He seemed to me a useful type of modern-day Prospero.'
I was intrigued that he called Lean a little man, partly because I wasn't sure it was an accurate description, but also, as I told McCowen, because his Prospero was the tallest I'd ever seen him. He positively bawled back at me 'Thank you] That's terrific. It's all in the mind of course. When I was a young actor, a student, I saw Gielgud play Hamlet, I saw Olivier do Richard III and I saw Richardson do Falstaff, and they were like giants to me, not just gigantic performances but they appeared to be actually physically larger than life. I think they cast a wicked spell on my generation, the big three, because most of us just assumed we couldn't do it too.'
After all, there is a tinge of regret about the way things have panned out. The 'wicked spell' didn't in the end deter him but 'it made me a late starter in the classical sense. I didn't join the Old Vic till I was 34. Maggie Smith joined at the same time, Judi Dench was there too, so it was a lovely company. But the daunting image of Gielgud, Richardson and Olivier was always at the back of my mind. It didn't stop me having a go at Hamlet and I did attempt Antony (in Antony and Cleopatra) though not to my own satisfaction. But at least I tried.'
At a time when he might have been essaying Richard III and Iago and Macbeth, he was, as he put it, 'waylaid' by worldwide success in a succession of one-man shows, first in the reading he conceived and edited from St Mark's Gospel, then in his digest of the writings of Kipling, finally in a sprightly selection from Shakespeare, Cole and Co. Combining as they did the judicious with the portable, these enticing packages took him all over the globe.
There was a down side, however, apart from rendering him unavailable for roles he might have played. 'One-man shows are all very well for hogging the limelight and having the stage to yourself. But it's a bit miserable before and after. Hotel rooms finally get you down. There you are, all alone in the Hong Kong Hilton. I think of the loneliness of Prospero. A lot of the parts I've played have been very lonely.'
Joining the Royal Shakespeare Company, of course, invites you to embrace the role of Company Man. To its recruits, the RSC is the collegiate troupe par excellence. Freshers receive an information pack to rival anything offered at our old-established universities. All the skills can be learnt or buffed right there, as it were, on campus.
I wondered if Alec McCowen felt like a Company Man. 'I never used to. I was happy at the Old Vic but I wasn't happy here 30 years ago. It was difficult for a single man being in Stratford. I resented the green room being full of prams. It's a wonderful job for actors with families to come and settle in their cottages and gardens.'
While even as long ago as the early Sixties it was easier to be gay in the theatre than in most other environments, McCowen feels a greater degree of tolerance in the profession now. Back then, he recalls, 'there was a division. On the one hand there was the Binkie Beaumont management in the legitimate theatre and Ivor Novello and Noel Coward in the musical theatre. On the other there was Jack Hawkins. And . . . well . . .' - he dissolves into mischievous chuckles - 'I'm sure we can think of some other great actors who were straight . . . if we think hard enough.'
His father loomed large in the early years. 'I think I've made a journey in my life, both in private and professionally. Certainly I started as a young actor using the fact of being an actor to get into disguise. I was clever at disguising my voice, putting on heavy make-ups and shrinking into another character. But I was very overawed by my father and I think I was in disguise from him. I adored him but I didn't think I was the son he wanted. He towered in my private life, rather like the image I had of the giants of the stage. I look at his photograph now and I see he was quite a little man and I wonder what on earth all that was about.'
McCowen recalls Arthur Miller's great play A View from the Bridge having to be mounted under club conditions to avoid the attentions of the theatre censor, all because two men kissed. His father declared: 'I would not like your mother or your sister to see a play like that.'
The conflation of notions of innocence, corruption and propriety leading McCowen pere to a ludicrous conclusion speaks of the tenor of the time. 'It's like a house of cards that will collapse with one wrong move,' reflects his son. 'But my father was terrified going into a theatre that, being the son of a shop-keeper and not having gone to university, he would be at a terrible disadvantage. A modern theatre like the RSC makes no such divisions. I watched Lear the other week and there were obviously a lot of people in this huge theatre who don't go to Shakespeare very often, but I've never heard such quiet. It was wonderful, like a religious experience.'
Throwing off the father brings us back to The Tempest. In this new production by Sam Mendes, there's a climactic, heart-stopping moment when Ariel, Prospero's 'tricksy spirit', flatly rebuffs his master at his moment of release (it would be callous to reveal the detail). McCowen is gracious about the RSC's resident Young Turk, Simon Russell Beale, here expanding his range still further as a djinn of robust delicacy. 'It's wonderful to be on stage with an actor of that authority and whom you can trust and experiment with. I guess he's unusual casting but it's such a relief to have an Ariel with whom I can have a really abrasive relationship instead of the usual rather wimpy little spirit.'
McCowen sees much that is contrary and even vindictive in his new character. 'But there's also the extraordinary side of the magic. There's huge buoyancy in that great farewell to the spirits of the island who seem, since he failed with Caliban, a family we know nothing about. I see it in terms of great relish and enormous fun, a secret life. He talks of 'midnight mushrooms'. What were they all up to?'
'The Tempest' opens on 11 Aug and runs in repertory at the Royal Shakespeare Theatre, Stratford-upon-Avon, until 29 Jan 1994