Andie MacDowell cried while filming Four Weddings and a Funeral sequel

They sit side by side in the front row, surrounded by their friends: John Hannah’s Matthew, Kristin Scott Thomas’s Fiona and Anna Chancellor ’s “Duckface”. Even in between takes, the atmosphere is lively and celebratory as the cast reminisce about the last time they were all together, two and a half decades ago. Newell does a lot of shushing before the cameras begin rolling again.

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As the cast pause for lunch, Andie MacDowell, in a long, floral dress, sits down to talk. Just behind us, Rowan Atkinson spoons potatoes on to his plate, dressed in priestly robes and ready to reprise his role as the hapless Father Gerald. “I loved seeing everybody again,” says MacDowell, 60, “because apart from Anna [Chancellor] and Hugh [Grant], I hadn’t seen them in years. Before we started shooting, we all had dinner together at Richard’s house and there was really good food, speeches and it was romantic, as it always is with Richard.”

It’s not only Curtis who is emotional about this reunion; MacDowell feels it, too. “I’ve been teary-eyed the whole day. It’s kind of silly but when you get older and you have the opportunity to be put back into a similar situation with these people who you had such a close connection to and you had such good memories of, it’s really affecting.”

Was there anyone who makes her feel particularly nostalgic? “I love John Hannah. He’s so down to earth, and seeing him brought tears to my eyes, he’s a genuinely beautiful person and when he read the WH Auden poem Funeral Blues in the original, it was quite something. There’s a little taste of that feeling in this Comic Relief version; you’ll get that same sort of emotion from him.”

It never occurred to MacDowell that she’d ever play Carrie again. Since 1994, alongside her modelling work, she’s had parts in smaller TV series and independent films, with supporting roles in blockbusters like Magic Mike XXL and a critically praised turn alongside Chris O’ Dowd in Love after Love, a 2017 film about death.

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Twice married and now single with two daughters in their 20s (Rainey and Margaret) and a son in his 30s (Justin), MacDowell has mostly stayed out of the spotlight at her home near LA. Before she was asked to do the Comic Relief special, MacDowell had been to Britain to join Greg Davies in the BBC3 comedy Cuckoo. “I love working in England, I think British humour is the best. British actors are very well trained and I like British crews. I loved working with Greg, he has no problem with being as far out as possible.”

Back in California, MacDowell received an email from Curtis about reprising her role as Carrie, and she responded immediately with “Count me in”. She was just as quick to say yes to Curtis’s low-budget film all those years ago, despite at the time already being a big American superstar after 1989’s Sex, Lies, and Videotape and 1993’s Groundhog Day

She’d been offered “a lot of money” for a different Hollywood film in the US at the same time, but came over to work with the relatively unknown Grant and Curtis on a budget of around £3 million because she was so enamoured with the script. “There wasn’t a doubt in my mind. I watched a clip from a church scene with Rowan and I knew it was gonna be a hit. It wasn’t made for a lot of money but it felt rich and beautiful. When I met Hugh I knew it would be easy, he was adorable and charming.”

Grant may have been adorable, but at the time he was far less famous than MacDowell. “People didn’t really know who he was, but after this movie he was a huge star. One of the funny things we used to talk about was his dilapidated car, whereas now he has Ferraris, so he can no longer tease me about having anything nice!” What’s her relationship with Grant like now? “I see him a few times every year. We have a huge bond through the success of the movie, because it was the beginning really for him, that was a big announcement to the world of his talent. He’s very sweet and funny, and we both feel deeply connected to Four Weddings.”

Grant, who for years afterwards was typecast as a posh, charming heart-throb, recently said he’s too old for romcoms and that as a result he’s getting “more varied” parts. MacDowell says she devoured Russell T Davies’s A Very English Scandal, in which Grant brilliantly played the reptilian MP Jeremy Thorpe. “I’m sure it must feel really cathartic to not just be seen as a romantic comedy lead but to do a really powerful dramatic role. I sat down and watched the whole thing, I loved it.”

While Grant’s character in Four Weddings was a lovable, sensitive Brit, MacDowell played the sardonic, colder American love interest, not as obviously charmed by Charles as the viewers were. “The hard part about Carrie is that she went off to marry someone else,” she says. “My disappointment in her not choosing him was the hard part of the role, and it was really difficult to make her warm because of her choices.”

Was MacDowell harder on Carrie because we are taught that women must be likeable and approachable, while men can be lovable rogues? “Yes that’s definitely true,” says MacDowell, “and what I felt, even though it wasn’t in the script, was that she was marrying this other person [Hamish] because she was doing what she thought she should do with her life, instead of doing what she wanted to do.”

As mother of the bride today on the Comic Relief set, MacDowell’s Carrie looks emotional and happy as her daughter walks down the aisle. She feels the character has changed. “I think she’s much looser, not so much high-fashion, less serious, more of a free spirit. I hope people see a softer side to Carrie now.

“Richard and I talked about our belief that she became a more laid-back person after getting together with Charles. Even in that short moment today it was nice to have the opportunity to evolve the character and make her comfortable in her skin.”

Lunch is over, and the actors are ushered back to church for more filming. Nicola Walker, who 25 years ago played the irritating folk singer, starts singing at the altar as MacDowell and Grant look on together. Atkinson stands up and begins Father Gerald’s stuttering sermon. Newell tells everyone to be quiet again, and Curtis looks dewy-eyed. This may not be a real wedding, but it feels like a momentous, poignant and love-filled celebration all the same.

One Red Nose Day and a Wedding will air as part of the main Comic Relief 2019 show on Friday 15th March at 7pm on BBC1