Agatha Christie's The Mousetrap, starring Susan Penhaligon, is coming to the Kings Theatre, Southsea

And the Agatha Christie play is coming to Southsea, with acclaimed actress Susan Penhaligon playing the pivotal role of Mrs Boyle.

She has joined the tour for a five-month stint through until the end of the year, and as she admits, she wasn’t familiar with the story until she was up for the part.

‘I’m really enjoying it,’ she tells The Guide. ‘It’s been a revelation to me – I didn’t know it, I hadn’t read it, I never thought I’d be in it. I always just thought: “Oh, it’s that play that’s been going forever”.

‘And then it arrived for me to read, and I thought: “My gosh, this is quite good!”’

There is a tradition with The Mousetrap of audiences being asked not to reveal ‘whodunnit.’

‘Agatha Christie based the play on a real event, which I didn’t know. It was a child abuse case just after the war, a big case, where these two Welsh kids were sent to live with a farmer and his wife in Shropshire, and he basically beat one of the kids to death. Agatha Christie obviously saw this case and wrote the play around it.’

It’s not Susan’s first brush with the record-breaking crime writer – she appeared in a tour of Verdict in 2011. Why does she think Christie’s works remain so popular?

‘She’s phenomenally successful and well-liked – she’s the second most popular writer globally after Shakespeare. And The Mousetrap is iconic – the audiences actually cheer at the end.

‘She’s a master of plot and character. She also creates these off-the-wall characters, which are quite attractive to play for an actor.’

While Penhaligon has been an actress since 1971, it was appearing in 1976’s heavyweight ITV drama Bouquet of Barbed Wire which made her name.

‘It was a game changer for me – it gave me a profile and it was at a time when there were only three channels and 26m people watched it.

‘You don’t get those figures now. It was an instant fame, if you like, which I was ill prepared for.’

And while much TV and film work followed, she has been a regular on the nation’s stage and still enjoys the travel aspect.

‘I think most actors are gypsies at heart, even if you’re doing films, you’re on location – it’s part of our job.

‘In some ways it gets tiring because I’m getting older, there’s no doubt about that, in other ways it’s a privilege – we really get to see Great Britain, and you get to see what’s really going on in towns and cities around the country.’

After her run as Mrs Boyle finishes, Susan doesn’t know what’s next, as she says: ‘I just wait and see what’s offered.

‘When you’ve been working as long as I have, you look back on the parts you played when you were younger – I had a terrific time, I was on television a lot, I did films, but I can’t play those parts now because I was in my 20s.

‘You change and you evolve and you hope that the casting directors and those who decide what they want will look at you in a different way – they’ll see you’ve got a few more lines on your face, unless you’ve had a facelift, of course,’ she laughs, ‘that you have moved into more mature roles.

‘The challenge of other actors competing never stops no matter how old you are.

‘And of course as you get older the roles, particularly for women get less.

‘That’s the reality of being a long distance runner in my business.’

The Mousetrap

The Kings Theatre, Southsea

October 14-19

kingsportsmouth.co.uk