Martin Shaw, the star of The Professionals and Inspector George Gently, talks about playing a new detective in Patrick Hamilton’s thriller Gaslight which is at Bath Theatre Royal this week

You’re leading the cast of Gaslight. What’s it about?

Well, it’s a thriller with some serious overtones. It’s a 1938 take on something that’s been going on throughout history, the coercive control of a partner by a man. Women have been fighting and subjected to this, throughout history. In this instance, the man, Jack Manningham, tries to convince his wife that she is mad in order to get rid of her and put her in an asylum.  Jacks wife, Bella, finds rescue in the form of retired police Detective Rough, who learns all about the situation and steps in.

You’re playing that retired policeman, Detective Rough. What’s he like?

He’s a very interesting, compassionate character. He’s driven because he knows something about Jack and is determined to solve a lifelong case in question. There are lots of threads running through the piece.

Why did you want to be part of this production?

I’d been looking for a play to do for some time, then this one came up. With the possibility of getting to work with Lucy Bailey, who is an extremely exciting director, it all came together.

What was it about working with Lucy that excited you?

I haven’t worked with Lucy before, but she has a reputation for being uncompromising, daring and putting a new shape on things. This is an old, Victorian-style, melodrama, but she’s added some rather spectacular effects. They’ve gone down brilliantly so far. We’ve had audiences cheering and standing, so obviously it’s satisfying people on a very deep level.

Patrick Hamilton wrote Gaslight as a play, but there’s also an Oscar-winning film version. What does seeing it on stage bring to the experience?

Oh, you’re absolutely part of it. You’re right there in the atmosphere of it. And when I say atmosphere, I mean that word very accurately. You are in it. It’s an experience with real people rather than with a screen.

How do you feel about taking the production on tour?

I think it’s very important to tour. I think people in the so called provinces deserve as much excellence as anybody in London, perhaps more so, because they are often starved of it. I think it’s part of our duty to tour as well as being simply a practical way to see what different audiences respond to and what they don’t.

You’ve worked with producer Bill Kenwright extensively over the years. What keeps you two collaborating?

I have! This is a partnership that’s been going for 36 years, so we know each other well by now. Originally, Bill was an actor and we were contemporaries. When he decided to become a producer, he staged a searing drama by Clifford Odets in 1983 called The Country Girl. I played Bernie Dodds. It was his first massive hit; people were queueing at the box office. That cemented a friendship. Ever since then, every couple of years or so we do a play, providing I’m available.

You started acting at school. What grabbed you about it?

I honestly don’t know. It’s something that I felt I knew how to do instinctively. It just comes to me. Of all the creative things that are possible, this is the one that I seem to be able to do best. I started when I was 14 and I don’t know anything else. I’m just as passionate now as I was then, probably even more so.

You’ve built a career spanning more than 50 years. What have been the highlights?

The Roman Polanski Macbeth was definitely a highlight, because who wouldn’t want to work with one of the world’s greatest directors and play a leading role in a Shakespeare film. It doesn’t get any better than that.

And I waited many years to be able to play Thomas More in A Man For All Seasons, which I did in 2006, so that also was a definite highlight. I’d waited to do it since I saw the film in 1968 and thought it was some of the most perfect writing I’d ever come across. Every other word I thought, “I wish I could say that, I’d love to be able to say that.” Eventually the chance came up. I’d do it again in a shot, just for the pleasure of saying those beautiful lines.

Are you looking forward to touring to Bath?

Bath is simply one of the most beautiful places in the world. It is certainly my favourite venue to work at because it’s a Georgian theatre and they really knew how to make theatres in those days. There were no such things as microphones and speakers, so they understood simply by experimentation what had the best acoustics. It doesn’t get better than going there.