Caroline Catz plays Louisa Ellingham

What was the reaction from viewers to the final series of Doc Martin?

It was a lovely experience having people coming up and saying how much they were enjoying it and how they didn’t want it to come to an end. It is really sad that it is over. It has been such a huge part of my life, and my family’s life, but it is absolutely the right moment to close the book on our story.

I am excited about that, there are new things for me, but also because it has been so successful and it has given so much happiness to so many people, including all of us who are in it. It is a winner for all.

You have been in Prague filming a new project were you able to watch the series as it was transmitted?

I have been watching Doc Martin mostly on catch up. I have just finished filming in Prague and it is lovely to be back here and hearing everyone’s reaction to Doc Martin. It has been such a loved show.

I haven’t actually watched the final episode because I can’t honestly bear to watch it. I decided I have to find the right moment to do that because I am going to be really sad. I got so many texts and emails and phone calls from people who were really moved by it, and thought it was a really beautiful ending.

Do you remember your final scene?

My final scene was with Eileen Atkins, in the kitchen of the Doc and Louisa’s house for the final episode. Eileen and I got there a bit early before we started rehearsing the scene, and Nigel Cole the director, put music on in the studio for us. So Eileen and I had a little dance in the kitchen to the Rolling Stones. That was probably the highlight of the series - having a kitchen disco with Eileen. Eileen has definitely got some amazing moves. We did have a laugh. Then I did the scene, burst into tears and left, and got a plane to Prague.

What was it like filming the final scenes and saying goodbye to the cast, crew and Port Isaac?

It was terrible getting in the car to finally leave. I finished the scene, and Martin bought me a really beautiful present and wrote me a lovely card. I went to say goodbye, burst into tears and said ‘I don’t want to go’.

I also had to say goodbye to little Elliott who plays James and that was a heartbreaker. He was so sweet, he was worried about saying goodbye to everyone as well. I gave him a little gift and we said our goodbyes and he was adorable. He was bought a bike by the production. My last memory when I was driving away was was waving at Elliott, but by then he was so ensconced in his new bike all the sadness was gone and he was very happy.

It is ridiculous how good Elliott is. He is such a wise little guy and was always making us laugh our heads off, which was a bit of a problem some times. Sometimes we would be in the middle of a scene and he would say ‘sorry, can I just say something’ and he would come out with a little musing. He is a very special little kid. I am sure he has a career in acting ahead of him. He has such a winning approach.

We all had a lovely barbecue and party on the beach on the Friday evening before we finished filming. Jessica Ransom ( who plays Morwenna) and I went for a swim at Port Gaverne before the party. Our families were there. It is such a special place.

Did you take home a souvenir from the production and/or Port Isaac to remind you of the 18 years you have been working on Doc Martin?

I was very lucky I got a very beautiful painting which had been on the wall outside Martin and Louisa’s bedroom.The painting, by a local artist, was of all the roof tops of Port Isaac, from the harbour wall. The art department said it was the first painting they bought in an art gallery in Wadebridge when the series started in 2004.

I love it, and it now sits in my house and makes me happy every day.

I came away with a couple of Louisa’s dresses and a couple of really nice knitted tops made by a company called O’Pioneers. The knitters who made the tops had a WhatsApp group, and they told me would message each other when they spotted Louisa wearing one of their knits.

You filmed the Christmas special in February, before starting filming the final series, what was it like seeing Port Isaac dressed for Christmas?

To be there in February, and to make February look like Christmas when we had all just packed away our own Christmas decorations was quite strange. It was beautiful to see it all lit up with Christmas decorations every where. I guess it was a bit puzzling for the tourists because suddenly there were Christmas decorations hanging from all the lamp posts and the shop windows were dressed.

The weather was challenging - there was a major storm Eunice— how did that affect filming?

We were filming in a studio in a barn and we were safe in there, but there were all sorts of things flying around outside.

I got a call from my mum who had seen the news about the storm hitting Cornwall, and asking me if I was OK. I went back to the back of the studio to talk to her and I was telling her we were all OK, and we were being well looked after when one of the sparks shouted over to me to say my hair was on fire. I was standing by a light trying to keep warm, and my pony tail was up against this massive light and there was smoke coming from it. I had no idea. My mum heard this and I had to reassure her.

What happens in the Christmas episode?

We have a very disappointed James on our hands because he didn’t get to meet Santa, and a very indignant Doc Martin, and it is baby Mary’s first Christmas.

Louisa doesn’t want James to be disappointed and when she tells him about the lantern parade in Portwenn when she was a child he asks her to organise one even though it is Christmas Eve the following day. He is so persuasive Louisa decides she will try to organise a parade. But unfortunately in true Doc Martin style, there are many complicated events that happen to hinder this happening in a smooth way.

James is really upset when he sees his dad having an argument with Santa and he runs away. Louisa and Martin are absolutely distraught until they get a call from Ruth to say James is safe with her.

Louisa is terrified something awful has happened to Martin when he doesn’t return to the village after treating a patient. There is this constant peril and tension all the way through the episode, whether or not they will be reunited, will Christmas ever happen.

It is a very beautiful Christmassy episode in this lovely snowy backdrop of Port Isaac, in a way you’ve never seen it before. It is a really lovely way to close the book on the story. It is another ending, but a very final and very beautiful one and funny too. There’s aways a twist at the end, never straight forward, and quite apocalyptic.

What are your own favourite Christmas memories?

Decorating the Christmas tree with our kids has been a lovely thing as a parent. I definitely identified with Louisa’s enjoyment of getting a Christmas tree.

Our Christmas tree does look overly done, certainly not a tasteful Christmas tree. I just throw everything at it.

What is your favourite Christmas present?

My husband and I give ourself the gift of no Christmas presents to each other which takes the pressure off us so we can focus on kids and family members and not get in a tizzy about what to get each other.

You have been away from home filming for much of this year, you must be looking forward to spending time at home with your family? Do you have any plans?

It’s been a brilliant, exciting, nourishing year full of really great work, so I am very happy to be back at home in London with the family. We are staying home for Christmas, and really looking forward to that.

You have done the voice over for the documentary Farewell to Doc Martin, which will follow the transmission of the Christmas special.

It is a lovely way to say goodbye to Doc Martin.

You started work on a new project soon after finishing filming Doc Martin?

I flew to Prague to film A Small Light, which is an eight part Disney series, following the story of Miep Gies, a Dutch woman who risked her life to shelter Anne Frank's family from the Nazis for more than two years during World War 11.

What is next?

A Buffalo Pictures production about Barbara Hulanicki who founded the Biba store.