New TV adaptation of Chichester novelist Kate Mosse's best-selling Labyrinth

On TV will be Channel 4’s big Easter weekend two-parter, a stunning dramatisation of Kate’s number-one best-selling novel Labyrinth.

“I don’t know what people will think of it, but the one thing I can say for certain is that the whole experience of it all was the most amazing thing for me,” Kate says.

She’s maybe not quite ready to watch it with family and friends, but she can honestly say she is delighted with the result.

Starring John Hurt, Tom Felton (Harry Potter) and Jessica Brown Findlay (Downton Abbey), it was produced by Ridley Scott’s production company Scott Free and keeps beautifully to the spirit of the novel, Kate says – an adventure thriller which has won her millions of readers.

“I have already seen the whole thing,” Kate says. “They sent me a rough cut DVD so that I could see it privately. It was an extraordinary and personal thing. I watched it on my own at home, and I watched it all the way through, and by the end, I had tears in my eyes.

“I really felt that they had been so true to the spirit of the book. There are wonderful performances, and it was just as I had imagined it. In the end, it all comes down to the story of extraordinary women eight centuries apart.

“We were approached by Hollywood when the book first came out, and they wanted to turn it into another adventure story with a male lead. But the whole point about Labyrinth is that it is an old-fashioned adventure story but with women as the heroes.

“You accept that what works on the page might not work on the screen and that changes will have to be made. But they said that they even saw Orlando Bloom in the lead!”

Kate held out – and in the end got exactly what she wanted: “Four or five years after Labyrinth was out, Ridley Scott (Gladiator, Robin Hood, Prometheus) said he would like to make it into a film for TV, what is called ‘event TV’. At that point, we just thought ‘Yes! That would be terrific!’ His track record with historical drama is amazing.”

And at that point, Kate decided that her role as author was to sit back “rather like the maiden aunt on the sidelines”: “I had no official role, but they asked me about everything. Every big piece of casting they asked me about. They asked me about the screenwriter.

“My decision was that you need to choose someone who won’t let your work down by doing a version that is not faithful. When you have made that decision, my feeling is that you have got to respect the professionals. They know about film, and I don’t. And you have got to let them deliver their vision. Everything they wanted to do that was a slight change they asked me and I let them every time except once; and every time with the casting, I said: ‘If you think they are the right person, then absolutely!’

“You have that respect for them, and the lovely thing is that they then feel able to ask questions. That’s why I had such a brilliant time. When I was first on set, all the actors came with their copies of Labyrinth for me to sign. They had all read it and were asking questions. Several members of the film crew said that the whole thing felt like a theatre company; everyone worked so well together and was passionate about getting it right.”

The film was made in south-west France where the book is set and also in South Africa where the weather, at that time of year, was much more reliable. Kate visited the set twice in France and twice in Cape Town – and even makes a cameo appearance in the film as a tour guide. The idea was to underline the point that though the work is a novel, it is based on history.

And that cameo gave her one of the most remarkable experiences of all: saying her lines, she glanced across and saw John Hurt and the others as characters she had created in a story she had written, a story which was now coming to life before her very eyes…