Inside this elaborate pyramid there is a swivel chair, on which she will spend each performance. But first it is going to be fitted out with a couple of additions. One is a back support. 'Like they have on secretarial chairs.' The other is a neck support. 'Because, can you believe it, that releases the muscles for your eyes.'
She pulls her neck back and rolls her eyes round to demonstrate. Then she waits and watches for me to follow suit. When someone's credits include Queen Caroline, Queen Victoria, and Queen Elizabeth II, not to mention the imperious Sybil in Fawlty Towers, you end up pulling your neck back and rolling your eyes round too.
It is seven in the evening and she has been rehearsing since 10am. Hard work, when it is almost a one-woman show. This is a five-week rehearsal, which is just as well, as she is a slow learner. That day, she announced with pride, she had got through Act Two and only dried up twice. After the interview I leave her sitting in the corner of the room dictating her part into a tape-recorder.
Is Happy Days physically demanding too? 'I can't tell yet.' She hesitates; she has this nervy, pent-up quality, as if her self-control is battling it out with a mission to explain. 'All right, I will say this. I think there is a misconception in the public's eye about the disadvantage of physical constriction.' Really, what's that?
'Everyone said how brilliant of Tom Conti to be in bed in Whose Life Is it Anyway? and only have his head to act with. He should be so bloody lucky] I'm not for a moment disputing that Tom Conti is an absolutely brilliant actor. But he should be so lucky to be stuck upstage in the spotlight, with everyone focused on him. Nobody looking at anything else for a second. Everyone came on and - ' She gets up and does the other actors turning their backs to the audience. 'The focus is not a disadvantage. It's plus, plus, plus. It's money in the bank.'
While she does Beckett in West Yorkshire, her husband of 30 years, Timothy West, is doing Arthur Miller in North Wales. They meet up at home in south London at weekends. Three of their four parents were actors. One of their two sons, Sam, last seen as Leonard Bast in Howards End, is at the National this week to rehearse Arcadia, the new Stoppard.
Small wonder that she is protective about her profession as a whole. She served for a couple of years on the council of Equity, the actors' union. She still reads The Stage, though not, presumably, for the ads. We start by talking about Beckett and she spins off into why on earth the Treasury takes away Schedule D self-employed status from young actors and puts them on PAYE. It is 'punitive'. The lack of government funding, in general, is 'terribly depressing'.
The interview is fast becoming a lecture when she changes gear with a hoot of laughter. 'That's the political bit] OK]' The political bit is one reason why she is here. She first met the director, Jude Kelly, then running the Battersea Arts Centre, at a women's section meeting of her local Labour Party in Wandsworth.
After Happy Days, Scales's brave year continues with the lead in The Matchmaker at Chichester. In 1955 she was in Tyrone Guthrie's Broadway production. She was 20, had a tiny part, and kept sane by taking lessons in method-acting from Uta Hagen. She still uses the approach: intentions, motivations, objectives. 'I'm not bothered terribly about terms.'
What is hard about television is the speed. Take Fawlty Towers. 'John Cleese is a very fast worker and a highly disciplined one. He was able, in the space of a week, to be absolutely ready to go and . . . ' She clicks her fingers. 'He could really blossom on the one performance we had in front of an invited audience on a Sunday night. I never felt ready to go. I love long runs. I never feel ready to go till about the second Wednesday matinee.'
As Anthony Hopkins's wife and Jeremy Irons's lover in the film A Chorus of Disapproval her wide, pained face spelt out the longings of a middle-aged mum. The territory is wide: from Sarah in BBC1's After Henry, which ran to 40 prime-time episodes, to the Queen in Alan Bennett's Single Spies. When you see the Queen now, you wonder why she keeps pretending to be Prunella Scales.
'It was extraordinarily enjoyable, from my point of view, because of the blasphemy factor. You come on, looking as nearly as possible like the Queen; the attention was wonderful. I suddenly realised how terribly famous people must feel.' Similar, perhaps, to being up to your neck in scorched earth. 'You suddenly have all this focus.'
'Happy Days' previews Thurs, opens Sat (press night 23 Feb) at the West Yorkshire Playhouse in Leeds (0532-442111).Reuse content