Doc Martin stars Sigourney Weaver and Selina Cadell reveal their 40-year friendship

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So the American went to see Doc Martin, handed his long-suffering receptionist a copy of The Assertive Female and was surprised by the doctor’s forthright manner. When she suggested he might feel better if he smiled, he pretended her accent was impenetrable.

None of Doc Martin’s seven million viewers could quite believe their eyes. What on earth was the star of Alien, Ghostbusters and Avatar doing in the sleepy village of Portwenn? The answer, in fact, is simple: she has been best friends with Selina Cadell, who plays Mrs Tishell, since they met in 1974.

So how did the guest role come about? By chance, Weaver was on The Jonathan Ross Show with Martin Clunes and told him she had always meant to visit Cadell in Cornwall – whereupon Clunes’s producer wife Philippa Braithwaite asked her if she’d like a cameo. It was so successful that Weaver is back in the jungle hat for this week’s final episode.

It’s initially a little strange to see Weaver, 68, and Cadell, 64, chatting in a break from filming. The former is a nearly 6ft, three-times Oscar-nominated film star; the latter, a comparatively diminutive 5ft 5in, is a versatile TV and theatre actor and director. Yet the two women get on famously.

We talk first in Weaver’s trailer, a minute’s walk from the converted barn that acts as an interior studio, and later at the St Enodoc Hotel in nearby Rock, where they often have dinner together. They do what all old friends do: talk easily and warmly, touch each other on the shoulder to show empathy – and laugh uproariously.

Selina Cadell on Sigourney Weaver

When my friend Peter first mentioned Sigourney, a friend of his from Yale Drama School, I thought it was an extraordinary name. Very exotic. Peter and I were to meet her in a pub in London’s Swiss Cottage that looked like a chalet and was surrounded by roads.

Sigourney was slightly late. I looked up to see this wonderful gazelle-like creature leaping over the small wall that separated us from the road. She was wearing a circular skirt, white ankle socks and trainers. I was struck by her height and incredible beauty.

It was the summer of 1974 and we were so young, still in our early 20s. She was only supposed to be in London for a few weeks, but she ended up staying for the whole summer.

We clicked and became close friends really quickly. Our backgrounds were in many ways very different, but in other ways similar; both our mothers had been to Rada [the Royal Academy of Dramatic Art].

Sig’s mother was the English actor Elizabeth Inglis, who appeared in Hitchcock’s The 39 Steps. I’ve never discussed this with her, but to me it made Sig feel more European.

New Yorkers can be quite intimidating, but she wasn’t. Anyway, we ended up spending the whole summer bombing around in my yellow Renault 4. We giggled until it hurt.

We’ve had a couple of moments when we’ve thought we were going to burst laughing. We have, for example, always shared a horror of people getting too intense for words about acting. Sig is more mischievous than the world realises. She’s like a little imp.

We’ve spent a lot of time laughing at things we shouldn’t, from evensong in Chichester Cathedral that first summer to the Actors’ Studio in New York. Laughter is a great glue.

After Sig returned to New York in the autumn of 1974, we talked on the phone quite regularly and I often got jobs in the theatre there so we frequently hooked up. When she got Alien, she left a message at the stage door of the Salisbury Playhouse in Wiltshire, where I was doing a panto.

I had to walk up to the roundabout to find a phone box, which I fed a never ending pile of coins because it was an international call. I was thrilled that she’d got the part of Ripley. My friend was going to be in a Hollywood movie! Plus it meant she would be filming at Shepperton and I’d see more of her.

Sig married six months before me in 1984 and asked me to be her best woman in Hawaii, where her husband Jim [Simpson] is from, but I’d been cast in Agatha Christie’s Miss Marple: A Pocket Full of Rye and couldn’t go. I was so upset.

Then she couldn’t come to my wedding because she was at the César Awards in Paris. My husband and I passed through Paris on our honeymoon. I noticed this woman at the station who was a vision in a midnight-blue floaty sequinned dress with some kind of duffel coat around it.

I thought, “What an extraordinary woman.” As we got closer, I realised it was Sig. She bombarded us with cooked rice, because it was the closest thing to confetti she could find.

She thrust a small Fortnam & Mason hamper into our hands that contained a little bit of everything delicious you can imagine. I have kept the crepe paper adorned with red hearts and the little champagne glasses. I keep my Christmas decorations in the hamper now.

I don’t want to get sentimental about Sig, but… I love visiting Sig in her house in the Adirondacks in upstate New York. When our kids were younger we spent holidays and Christmasses together, but now we mostly discuss work.

We admit our fears to each other, which is probably rare among actors. I’ve spent quite of lot of time reminding Sig that she’s a famous, brilliant, wonderful actress.

Filming Doc Martin together is a joy, but we’d love to work together properly, perhaps on a comedy. We still have such a giggle and she’s still the girl who jumped over the pub wall all those years ago. We’ve grown up together.

Sigourney Weaver on Selina Cadell

I loved Selina as soon as we met in that London pub. We stayed in touch the old-fashioned way after that first summer in London, sending letters and postcards. When I found out I’d got the part of Ripley in Alien, I phoned my parents and then Selina. I was thrilled that I was going to be filming in London.

When you have a friend who’s also an actress, but is as generous and as well-balanced as Selina, then you can call them up and tell them about a great job. There were plenty of friends I wouldn’t have been able to call, because their first instinct would’ve been, “Why am I not getting a movie?” But I knew she’d be happy for me.

Selina says that people don’t see me as she’d like them to. But Ripley didn’t have time to be mischievous – one person dies after the other in Alien – and often people’s perceptions of you are based on the first few films you do.

I’ve been very lucky to be in high-profile films, but I’m always looking for comedies. I’d love to do a comedy with Selina; we have stories that we work on periodically.

But she is very busy directing and writing and I’m filming Avatar 2 and 3, taking a break, then filming 4 and 5.

In the meantime, I’m so happy to be working on Doc Martin. She often talked about it, but I hadn’t realised it was a comedy. I kept trying to visit Selina here in Cornwall, but it never worked out.

Then, wonderfully, I was on The Jonathan Ross Show with Martin Clunes. He’s such a lovely guy and he beams with bonhomie. I had a drink with him and his wife Philippa in the green room and she suggested I come on the show.

I said, “Are you kidding? I’d love to!” They sent messages via Selina asking if I’d appear in series seven and again in series eight. Of course I did! I made Avatar rework their schedules so I could be here.

People expect me to behave in a grand manner, but it’s not like I’m John Travolta. Having a cameo in Doc Martin is a dream job for me. Cornwall is the most beautiful place. I’ve read every novel about it I can and I watch Poldark on my iPad.

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I identify strongly with my British heritage. I was sent on a plane on my own to meet my maternal grandmother when I was 11, which was thrilling. I remember saying to this sweet woman who’d had nine children, “You’re my bloody relation!” I thought it was so funny. She just shook her head and muttered, “This half-American child…”

I also spent a lot of time in Europe with my mother and we lived in France for a few years when I was 12. I’ve always been grateful to have had the chance to live somewhere other than America. My husband and I have watched every single episode of Escape to the Country and I’ve seen pretty much all of England while travelling to see Selina in various plays. Some day we might move here. I hear so much laughter around me in Cornwall. In America we’re not laughing nearly as much.

I admire you British: when things get tough, you reach for humour. Not firearms. I’d love to live closer to Selina, but however far away she might be, she is always with me. When I’m working I start each day by listening to a tape she recorded for me ten years ago. She tells me how to relax, how to catch my breath. It’s my safe place.

This article was originally published in November 2017