As an actor, Simon Williams first came to national prominence in the 1970s sitcom Upstairs, Downstairs. He later went on to appear on television in First Among Equals, Don't Wait Up, Return of the Man from UNCLE, Law and Disorder and Killer Net; and in films such as Jabberwocky, The Black Knight, The Prisoner of Zenda and The Fiendish Plot of Dr Fu Manchu.

Williams' many theatre acting credits have included: in the West End, A Friend Indeed, Hay Fever, His Hers and Theirs, The Collector, No Sex Please, We're British, Gigi and The Winslow Boy; and on national tour, An Ideal Husband, They're Playing Our Song, Deathtrap, Donkey's Years and 39 Steps.

Williams is also an accomplished author, having written two novels and three other plays, Laying the Ghost, Switchback and Kiss of Death. His latest play - Nobody's Perfect, in which he also stars - resumes an extensive UK-wide tour this month. The comedy, about a male romantic novelist who dresses up as a woman to win a writing competition, co-stars Stephanie Beacham and Williams' daughter, Amy.

Date & place of birth
Born 16 June 1946 in Windsor, Berkshire.

Lives now in
Nettlebed, Oxfordshire

First big break
Playing James Bellamy in Upstairs, Downstairs was my big TV break.

Career highlights
Upstairs, Downstairs was the first. After that, working with Nigel Havers in Don't Wake Up, and with Michael Crawford in No Sex Please, We're British. Michael is one of the funniest men alive. Then there were the two films I did with Peter Sellers - The Fiendish Plot of Dr Fu Manchu and The Prisoner of Zenda. Now is a highlight too - I think being an actor performing in your own play is one of the most exciting things you can do.

Favourite production you've ever worked on
The one I'm doing now is my favourite - it has to be, it just completely fills up your mind. Between the end of our last tour schedule and the start of our new one, the cast have been on hiatus for ten weeks, but still we've been on the phone all the time with each other with ideas.

Favourite co-star
Nigel Havers was the most fun. He's now my brother-in-law, he married my sister. The actress I've worked most with is my wife Lucy Fleming. She's brilliant to work with but brutally honest.

Favourite director
Ray Cooney. You think he's only a farce director, but he's a very good director of character too.

Favourite playwright
It has to be Alan Ayckbourn. He constantly swings you around, throwing a funny scene at you and then a moment of huge pathos. He's so creative and prolific too. He's on his 60-somethingth play and here I am struggling on my fifth. Ray Cooney is also a hero of mine as a writer. Somewhere between Ray Cooney and Neil Simon and Ayckbourn - that's the type of playwright I'd like be.

What role would you most like to play still?
I'm very frightened of Shakespeare because I've seen all of them played so brilliantly already. I'd love to have a crack at Trigorin in The Seagull or one of big old George Bernard-Shaw gentleman. More exciting than anything, though, is a new script. If Hare, Ayckbourn, Stoppard or Pinter called me up, I'd be more thrilled than anything. I wouldn't have anybody else's voice in my head. I dream of being adventurously cast. I want something to be brave in casting me in something unlike anything I've been in before. When someone tells me they've got a part that's "ideal for me", my heart sinks.

What play would you most like to have written?
I'd love to have written Noises Off by Michael Frayn. All the characters are completely fleshed out, and the plot that they operate within is such a brilliant piece of engineering. That combination of good character and plotting is what makes a good play.

How do you balance your roles as an actor & writer?
You know, it's like if you've got all day and just one letter to write, you can't write it. The more you do, the more you can do. And writing and acting are so different; I love mixing my day with both of them. It's very lonely and solitary writing while acting is almost too gregarious, so they balance each other well.

In your opinion, what's the best thing currently on stage?
In the West End, The Play What I Wrote and Humble Boy are two real treats.

What advice would you give the government to secure the future of British theatre?
Take VAT off theatre seats, especially now that we haven't got the tourists in so much. In London, we need to recognise the importance of the brilliant theatres we have and the trade they bring in. Regional theatres seem to be better appreciated by their audiences. On tour, when you go to a well-run theatre, it's always full of happy, smiling faces. That's how it should be. A theatre is very important, it keeps a town alive after the shops close, it generates a new life.

If you could swap places with one person (living or dead), who would it be?
As an actor, I'd swap with Jeremy Irons because he's always choosing and doing stuff that's terribly good and that I'd like to do. He's bout my age and size too, so they wouldn't even have to adjust the costumes. With my writer's hat on, it'd be Ayckbourn.

Favourite book
The PG Wodehouse omnibus

Favourite holiday destination
Cobblers Cove, Barbados

Where did you get the idea for Nobody's Perfect?
I'd written a couple of novels that were thrillers and I said I wanted to write a romance, but my publishing friends said if I wanted to do that, I'd have to assume a female nom de plume. I thought that was terribly unfair and the play came from that notion.

What are the advantages & disadvantages of appearing in a play you've written yourself?
The advantage is, if it's not working, you can rewrite it. The disadvantage is that, when it goes well, I think it's because the cast are marvellous, when it goes badly, I think it's because I haven't written very well. It's not as rewarding as you'd think, but I do still feel a bit pleased when the audience claps.

What do you like & dislike about embarking on an extensive tour such as this?
It's great to spend so much time with my daughter (Amy Williams) who's also in the play. There aren't many parents who get to see their grown-up daughter six days a week. I probably drive her mad. I love being at a different theatre - that's what keeps you fresh - but I don't like the different apartments. It's the change of pillow every week that drives me mad; I should get one that travels with me.

What's your favourite line from Nobody's Perfect?
The character who plays my father gets into a bit of pickle between lap-dancing and line-dancing and I think it's very funny.

What's the funniest thing that has happened in the run to date of Nobody's Perfect?
I have to dress up as Myrtle Banbury at one point in the play. There's plenty of time to get into the costume, but very limited time to get out of it. During the first week of performances, I was in such a panic getting out of the bra, I had to get a Stanley knife to slash my way out of it. You'd be surprised how hard it is to get them undone from the inside.

What are your plans for the future?
Nobody's Perfect is already settling in across Germany, Italy and Spain, so there's a certain amount of pressure to write a sequel. I hope it has a good life in this country; it'd be absolutely fantastic to take it into West End.

- Simon Williams was speaking to Terri Paddock

The new 2002 touring schedule for Nobody's Perfect opens on 14 January at Windsor's Theatre Royal and then continues to Brighton, Cambridge, Nottingham, Plymouth, Bromley and Coventry.