Only Fools and Horses icon Tessa Peake-Jones has revealed the "frightening" nature of what life was like working on the smash hit BBC show. In 1981, the first family of Peckham drove into our lives in a yellow three-wheeler van, with a dream that "this time next year we'll be millionaires". The BBC sitcom quickly became a national institution and is still entertaining generations more than 45 years after Derek 'Del Boy' Trotter (played by Sir David Jason), younger brother Rodney (Nicholas Lyndhurst), and Grandad (Lennard Pearce), welcomed us to Nelson Mandela House.

But in an exclusive interview with Express.co.uk, ahead of her upcoming role in the comedy drama stage show Invisible Me, the 68-year-old star has revealed the reality for the cast and crew working on the hit TV show. The TV favourite rose to fame as Del Boy's partner Raquel Turner and confessed that it was no laughing matter, preparing to walk out on stage for a live studio audience.

She told us: "It's really frightening because you have got several hundred people watching you. It's a very peculiar thing that I never quite got used to. If people had seen us backstage before the show, they'd have seen people pacing up and down the corridors with nerves, including David [Jason] and Nick [Lyndhurst].

"We cared so much, and we wanted to get it right, but one slip-up of a word could ruin that laugh." Before the Bafta-winning cast stepped into the studio, they spent countless hours in rehearsals, often leaving them struggling to see the funny side of things.

"If you're doing comedy, you find you don't want to laugh because then you break the reality of it," remembers the actress. "Usually, we've seen it all in rehearsals so many times, it's not that funny anymore anyway." It comes ahead of the 45th anniversary two-part special set to hit the airwaves this summer.

After filming Only Fools and Horses: The Lost Archive for comedy channel U&GOLD, the mum-of-two admitted it felt like "torture" watching the unseen footage back. She explained: "You're looking back at something 30 years ago, and we're all a lot older now, so you just look so different," reflects Tessa.

**** Ensure our latest showbiz headlines always appear at the top of your Google Search by making us a Preferred Source. Click here to activate or add us as a Preferred Source in your Google search settings. ****

"It was harder for David because some of that stuff for him is looking back 40 years, which I know he finds quite odd. It was nice spending the day with him because we don't get to meet up that often, but he said, 'Isn't it odd to see yourself looking so much younger?'"

She says the experience was even "quite depressing" and that she would not wish to repeat it. "You think, 'Oh, we were in our prime!' which is quite a weird thing to be witnessing decades later. It's a very odd experience. It was a bit like torture to be forced to sit on the sofa and watch this stuff back from 30 years ago, it really was, but it's part of the job."

The two-part special, out later this year, will feature interviews with cast and crew, and includes archive material from more than 10 classic episodes, including Christmas specials The Jolly Boys' Outing, from 1989 and 1992's Mother Nature's Son.

Speaking about her upcoming play at Southwark Playhouse, which explores romance and relationships later in life, the actress teased that it has allowed her to dip her toes back into dating.

She reflected: "This particular play is beautifully written by Bren Gosling, and what's lovely about the play is the title Invisible Me sums it up really, it's that thing that when you get to a certain age in your 50s and 60s, people stop noticing you. And that's for men and women; you're just not noticed as much.

"So, to look at that age group and then say, How about we try and get them back dating' is fascinating. How do you do that at 60 when you're not very good on the internet, and you're not great online? What do people do? So, I think all of that is really fun, and it's going to be quite an interesting play."

When asked if it has inspired her to get back out into the dating world again, she confessed: "It hasn't, but never say never. I think he's written it all really well. Each of us has got a slightly different way of getting our confidence back sexually. He does it quite slowly because they've been on their own for a while, and I think when you're on your own for a while, you forget how to flirt or how to chat someone up.

"I think it's probably easier for younger generations who've learned about emails and all that stuff from very early on. I mean, I can't use anything but my forefinger to type anything on my phone, and it takes forever. So, it's a training that we never had, so when you add that extra layer of how to meet someone, it makes things even harder."

Tessa Peake-Jones, James Holmes and Kevin N Golding star in the new comedy drama, Invisible Me, at Southwark Playhouse from April 8 - May 2. Tickets are on sale now via their website.