The making of Sunset Song: Phil Miller reports from the set and interviews star Agyness Deyn and director Terence Davies

After filming, we meet the cast in a tent, set up beside a B-road in the middle of this lush countryside. It is full of actors in period costume. The tent is noisy with talk and the clatter of cutlery: a movie being shot on location resembles a small, if peaceful, army on the move. The tent also contains, sitting with the extras and technical crew, the stars of the long-awaited film.

Visiting journalists are sat at a table, given (excellent) food and are visited by the various key actors, including Kevin McKidd, whose work on the film did not make the final cut.

Agyness Deyn, 32, sits down at the table. In her first major screen role, the former Vogue cover star, voted one of the top models of the 2000s, carries the weight of the film as Sunset Song’s heroine, Chris Guthrie.

Lewis Grassic Gibbon’s 1932 novel has Chris at its centre – growing up in a farming family in the fictional estate of Kinraddie in The Mearns, Kincardineshire, in the north-east of Scotland at the start of the 20th century. The story takes in family strife, generational friction, and the damaging effects of war.

Deyn, however, is full of bonhomie today. If that weight exists, the actor – tall, with her blonde hair arranged in a complicated plait – wears it lightly. “This is like speed dating,” she says, of her move from table to table in the makeshift refectory.

We meet in the midst of the shoot, and she seems overjoyed by the experience. “Working with Terence [Davies] is a dream,” she says. “Well, he is a genius, and a legend as a filmmaker. I remember watching that documentary, [Mark Cousins’] The Story Of Film, and he came on and I was like: ‘Holy sh*t, it’s Terence on the telly’. I started watching films in a different way after seeing his productions. Working with him – he is such a gentleman, so caring. He sees you, and nurtures you. I feel like it is a dream to do a role like this, with someone like this, for the first time.”

Deyn is on set every day, and on screen for the majority of the movie. “Me and Peter [Mullan, who portrays Chris Guthrie’s father] were talking about this the other day,” she says. “Obviously Peter has so much experience, I am learning so much from him. He said, ‘You know what Ags, it’s probably better you are filming every single day because then you don’t have the chance to think about it.’ I am just in it all the time.”

The process of being Chris Guthrie grew from some theatrical work she performed in London. “I was in The Leisure Society [at the Trafalgar Studios] in the West End, and the casting director came to see it, and I went up for a cup of tea and I felt like I was interviewing them: I asked what they were working on and they told me and I said ‘Holy sh*t, can I read it?’

She adds: “The script embodied the story of a woman trucking on through this male world, which I feel is really current at the moment. I was moved and I felt I had to figure it out.”

Deyn, who grew up in the north of England, had accent coaching with two specialists before auditioning for the role. "Yes, I felt I had to do this. I did a few days [of training] before auditioning.” By the time we meet, she feels she has the accent issue solved. “I have it, now I do,” she says. “Although today [on set] I am just crying.” As Sunset Song readers will know, Chris Guthrie has a lot of grief to contend with.

Deyn was aware of the iconic nature of the book. “It’s very Scottish, it is of the land,” she says. “But I feel also, and not in a way that is less Scottish, that if you have grown up in Britain, it is the same land – I feel like I know this land because I live on it – it is just a different terrain.”

Her childhood (she grew up near Oldham in Greater Manchester and later moved to Lancashire) was spent among landscapes not so far removed from those encountered by Chris Guthrie. “As a kid I was in my wellies walking the moors, being out there,” she says. “I really did feel that it was one thing that connected me [to the book].

“Lewis Grassic Gibbon was so ahead of his time,” she adds. “Obviously he was a male but he was writing about women in a way that no-one had ever written about women before, in this liberating way, which was unheard of back then.

“It was very risque at the time, and it still kind of is risque, now. It has that quality. You want to read it, it has this excitement that drives you, even though it is so old. It is magical.”

Deyn read the book for the first time after she got the part. “It was really moving,” she says. “The first section is hard to read.” (The novel’s prelude – titled The Unfurrowed Field – is notoriously difficult.) “I actually found a dictionary online, just specific to the book, because there was one word I couldn’t get and I couldn’t get past it until I figured out what it meant – or it wouldn’t have made sense.

“The dictionary made it easier, and as soon as I got the language, [Sunset Song's prelude] really informs the part. Obviously when you read a book, your imagination runs wild and that is what it did and it just consolidated it – it made the life in the book, live. The daily work and the hardship: and it is amazing the way Terence has captured that. The script has got all of that in it.”

A recent Vanity Fair profile of Deyn compared her to Faye Dunaway. “Yeah, I read that – I thought ‘Holy sh*t!’”

So are her modelling days over? “I always said I would never do a job that I didn’t enjoy, and I enjoyed modelling so much when I started. I did it for 12 years. I started like you do in any job – you want to advance and grow. Then I made a film and thought: this is what I should be doing, this is the next thing. And I thought: if I do both, then it dilutes the other, so that is when I decided to pursue acting.”

After Deyn returns to the set, we are joined by Terence Davies, lauded director of films such as Distant Voices, Still Lives and The House Of Mirth (shot partially in Glasgow). “We started auditioning [Deyn] and someone said, ‘Oh she’s a well-known model’, but I don’t know anything about that part of culture.

She got it purely on doing the best audition,” he says.

“She is fantastic – a major talent. It is a difficult role because she is in every scene, literally every shot. But she is extraordinary: today we were doing shots where she is young and she looks 11. We have done shots where she is married and she looks 30. She has given the most wonderful moving performance and one that is full of imagination and variety.”

He says Deyn has been a “joy to watch”, and noted the amount of work she did learning a new accent. “She has a very good ear,” says Davies, 70.

The decision not to shoot the film in the Aberdeenshire dialect of Doric was made, he explains, because the film needed to be comprehensible to a wide range of audiences. “If you cannot understand what people are saying then you are not involved in what you are looking at,” he says.

Davies’s love for Sunset Song dates back to 1971, when he watched the BBC TV drama serial starring Vivien Heilbron as Chris. “In those days,” says Terence, his soft voice bearing a hint of Merseyside, “you had to wait a week for the next instalment. I used to live for Sundays, because I thought it was wonderful.

“I went out and bought the book, but

I didn’t realise it was part of a trilogy

[A Scots Quair] and it was wonderful. I then forgot all about it, then re-read it one day, and I thought: this is such a great work – I will try and get some interest in it.” An effort to make the film in 2003 collapsed. “It has taken 15 years to make it,” he says.

“The most moving thing about the book,” he says, “is the story of Chris, the journey that she goes on. She is a schoolgirl, a daughter, a mother, an orphan, she is widowed – it’s an astonishing journey and, at the end, she becomes a symbol for Scotland itself. That is why it is a great work – it is beyond just a family, it is about the nature of being and suffering and forgiveness. And still managing to have hope. Because if there is hope, we can all go on, but we cannot go on if there is only despair, it is too painful.”

He likens the story to Anton Chekhov’s The Cherry Orchard “which has the same melancholy”, only with more warmth.

Though Grassic Gibbon was a noted left-winger, Davies insists his film is not a political work, either with a capital P or lower case p. “I am not a political animal,” he says. “I don’t read those things.

"Quite frankly, I am too emotional about it. I have always been socialist. I feel in my heart that socialism is right. But I can’t have political themes, it is just not my area of competence. I am more concerned with how people behave, and endure suffering, without becoming bitter. Also, I am interested in the poetry of the ordinary – that too can be political, it doesn’t have to be a grand thing.”

He adds: “A girl walking through a field. That can be as powerful as any great music or any great song.”

Davies acknowledges the book may have a socialist or egalitarian message at its heart, but that, to him, is “extraneous”.

“To me, the most important thing is human beings being changed profoundly by what they experience, and not becoming bitter – that seems to be the great achievement of Sunset Song.”

Sunset Song opens in cinemas on Friday