The excitement of being able to talk to the real life Marlene was almost too much for me. She is a revered name in our house and a constant catchphrase, mimicking her husband Boycie's dulcet tones in Only Fools And Horses

Here in Oxford under a different guise, but still under the comedy mantle, Sue Holderness is currently riding in the Olivier award-winning comedy Out Of Order, the political farce, and continuing to keeping everyone howling in the aisles. And yet despite her comedic history she is still astounded by the audience reaction.

"It has been astonishing, none of us can remember being in a show where people have laughed so much," she remarks, which is saying something, considering her pedigree.

As Boyce's long-suffering spouse in the much-loved BBC series, followed by five series of The Green Green Grass, Sue has certainly made a career out of making people laugh.

"I know! And there was me thinking I'd be playing Hedda Gabler at The National by now," she jokes. "In fact I played the granny in Chekhov when I was younger and thought I had been incredibly moving until a family friend came up afterwards and said 'I think you're going to make your money in comedy', so that was the first clue, even when I was fresh out of drama school," she laughs.

"And I loved live performing in front of a live TV audience. I loved the cameras, lights and laughter so yes it did seem to be the thing for me, and situational comedies became my forte." And some - Only Fools And Horses recently topped a chart of the most watched TV programmes in the 80-year history of British television, spanning seven series and securing its cast's longevity and fame in the nation's pysche.

"Yes, playing Marlene meant I could pick and choose and I will be forever grateful to Only Fools And Horses for offering me that opportunity. Of course I was always riddled with anxiety that I'd be found out, but we had 36 million viewers so people obviously liked us.

"And then it went further afterwards with Boycie in The Green Green Grass which was filmed at John Challis' actual house in Shropshire, where we all used to stay. His wife Carol makes wonderful cakes. We had such a lovely time."

So what's the secret? "To get laughs, comedy has to be truthful because you never know if people are going to like something. And that has certainly been the case with Out Of Order because we had no idea how it was going to go. It hasn't been done since 1989 but it is about being in dire straits, and you believe them and go along with them. We aren't telling you when to laugh, but if the audience believes in the characters and how much trouble they are in, that's what's so fun.

"So when Ray Cooney (the playwright) rang me and said I'm celebrating 70 years in the business and you're celebrating 50, what better way to do it? So it's a real honour and a bit of a special production because you never know what your next job will be as an actress.

"It's all about a politician having an affair with a secretary and something happens with a sash window and everything goes dramatically wrong, but I won't give the game away.

Would it happen these days? "I couldn't possibly say. In the old days they got up to all sorts of shenanigans. But what's great is that everyone is so fed up with Brexit, Trump and the referendum that this gives us some sort of escapism, and laughter is the best medicine. This will really tickle you.

"And it's a wonderful cast and Susie Amy looks quite delicious in her underwear. Luckily my part just relies on a bit of lipstick and a small cleavage, " she laughs.

As for touring, Sue is a pro with some impressive theatre credentials to her name, so does she mind the constant disruption?

"I've been married for over 30 years and I put my successful marriage down to my constant touring," she laughs. "I'd recommend it to anyone because absence does make the heart grow fonder.

"And as he went to Oxford (Magdalen), we often come down and have dinner at the High Table and absolutely love it. Oxford is so beautiful and we are confident about our erudite audience and encourage them all to come along. Because I've done a lot of comedy in my career but I can't remember people laughing like this. It's great."

Ray Cooney's Out Of Order comes to the New Theatre from Monday-Saturday. atgtickets.com/oxford or 0844 8713020