FROM the age of four, there was never any doubt in Louise Jameson’s mind that the stage was where she belonged.

“When I was four, I played Little Miss Muffet and I was a triumph,” she explains. “I remember standing outside and hearing everyone laughing and clapping and I thought, that sounds like fun.

“I took every opportunity that presented itself,” says Louise, who will be on stage in The Mousetrap at The Courtyard in June. “I got told off for not working on anything except English and drama. I’m not work shy, but I just didn’t want to do anything else. I was so single-minded.”

So fierce was her determination, that she secured a place at RADA at the age of 17. “I was ever so lucky,” says Louise, familiar to TV viewers of Dr Who, Tenko, Doc Martin and EastEnders.

“They did see me twice,” she says of her RADA interviews. “They called me back because I think they wanted to be sure.”

Going to drama school so young meant that Louise had completed her studies by the age of 19, and after leaving, she joined the Royal Shakespeare Company for two and a half years. “It was a bit like an extension of drama college,” she says. “It was a terrific grounding for everything else.”

It was when she was 26 that she won the role that gave her her big break and which, 40 years later, has, she explains “turned into my pension”. And that was the part of Leela, the Sevateen warrior and companion to The Doctor. “That job was just 14 months of my life three decades ago, and still I am remembered for it,” she writes on her website.

“My agent and I had been holding out for a TV series – I didn’t get Purdey in The New Avengers, the part that went to Joanna Lumley, nor a part as a nurse in Angels.” It’s hard to believe that either of those would have the longevity of Leela with Louise regularly attending Dr Who conventions around the world “on the back of that”.

Louise plays Mrs Boyle in Agatha Christie’s iconic The Mousetrap: “She is not an anchor of the piece. It’s a character role.” Despite its 64 years in continuous performance, the secret of whodunnit continues to be kept by audiences. “That little curtain speech (before the action starts) is lovely and people are very faithful.

“I was slightly worried about doing eight months on the road – I am of an age when it’s not quite as easy to adapt as it used to be! I like my en suite.”

“What I do love is the different theatres, which really helps to stop it getting stale – audiences are different in every one.” When we spoke, the show was in York: “They love me being grumpy in York,” she reports gleefully.

Even with a varied portfolio including extensive stage appearances and a wide range of TV roles, there is one that Louise points to as a favourite – playing Blanche Simmons in Tenko. “That was my favourite time,” she recalls. “Writers Jill Hyem, Anne Valery and Paul Wheeler did such brilliant research and completely trusted the actors.

“Blanche was a really tough young woman, a real survivor. I loved her. Every now and then a script lands and you feel you’ve been that person in another life and you have a strong connection to them,” she says of Blanche.

“We shot Tenko in a sandpit in Dorset,” she laughs. “We used to have to buy in yucca plants!”

The Mousetrap runs at The Courtyard from Tuesday, May 31 to Saturday, June 4. To book, call the box office on 01432 340555 or visit courtyard.org.uk