This wasn’t a movie about fashion; it wasn’t a movie about sex, all the things that I’m known for. No one shaved a G into anyone’s crotch. But it was the most creative and personal thing I have ever done.” Tom Ford, fashion designer, style icon and businessman, is talking about his feature film directing debut, a lyrical and unexpectedly powerful adaptation of Christopher Isherwood’s A Single Man. It’s a lovely, lush, romantic movie. But was making it really more fulfilling than being a multi-million dollar business concern or, personally responsible for the shot in the arm of sex and glamour that arguably saved Gucci?

“Yes, because that is commercial. Creative, but a commercial endeavour. This was really a form of pure expression, closer to the reason a painter paints. I hope people see it, but I wasn’t trying to make a blockbuster. I wasn’t trying to make an exploitative giant hit that I could buy a new country house with. Fashion is how I make my money and this was really much more pure.”

It’s an undeniably brave undertaking for someone who has already achieved massive success in another field to start again, virtually from scratch in a new art form. Ford had little margin for error. The slightest lapse of judgement and charges of dilettantism would rain down. But the sound of knives being sharpened quietened down almost entirely after A Single Man’s first screening at the Venice Film Festival. It is, by any standards, an accomplished and affecting debut. “I put so much of myself into it, it will be very interesting to see if people respond,” Ford says cautiously.

It’s a personal project on many levels. Before he had aspirations to direct, before he had even shaped himself a fashion career, Ford had a relationship with the material. He first read A Single Man in the early 1980s, when he had just moved to LA.

“I was living with someone at the time who just didn’t show up — he was supposed to move with me and he never did. And I developed a crush on George [the central character of the book, a bereaved, gay college professor living in LA in the early 1960s]. I fantasised that I was going to run into George somewhere even though I knew he was a fictional character.” Ford later met Isherwood and his partner Don Bachardy and became fascinated with what he argues is Isherwood’s groundbreaking approach to gay themes in literature. “One of the things I love about Isherwood’s writing is that there is always a gay character but he is never struggling with his homosexuality and he’s never being discriminated against. He is just a person who has other friends and a life.”

But it was not until he re-read the book in later life when he was looking for material on which to base a film that he really connected with it, finding a new spirituality in the story. There is, he says, a lot of himself in his cinematic interpretation of George. But while George, played by Colin Firth, has a taste for immaculately tailored suits and understated elegance, can they really have so much in common? Ford is dazzlingly successful, wealthy and in a long and happy relationship (with journalist Richard Buckley), whereas George is a broken man who has lost sight of the beauty in life and spends the film planning his suicide.

“Have I had a midlife crisis? Yes! Don’t write too much about it because I don’t want to dredge on. But, yes! I became very successful, very early. I had all the money I wanted, all the houses, I had been in the same relationship with someone for 23 years, I have two lovely dogs. But the emphasis I put in my life was materialistic. I have always had a spiritual side but I neglected it. And at a certain point in your life you realise, OK, I have all this stuff, but what does it really mean? You start to realise that it is those small things that your mother tells you when you are little — stop and smell the flowers.”

He launches into a description of the simple pleasures of cuddling his terriers in bed at night, burying his nose in their fur and revelling in their doggy smell, then stops short, apologetically. “I’m just rambling, I don’t know if I’m answering your questions.”

Ford was born in Austin, Texas to parents who both worked in real estate. His early life was spent in Texas and New Mexico, but at the age of 17, he moved to New York to study art history and everything changed. A habitué of Studio 54, Ford swiftly came to terms with his sexuality and his lack of interest in academic pursuits, dropping out of college and focusing on acting in television commercials, while simultaneously studying interior architecture. His first taste of fashion was in a low-level PR position at Chloé, but he soon moved up in the world, working with Cathy Hardwicke, then Perry Ellis. Then in 1990, the still unknown Ford was hired by Gucci, a mutually beneficial arrangement that left both parties wildly successful. Four years ago, Ford dramatically parted company from Gucci and subsequently launched his own perfumes, sunglasses and a range of utterly desirable but prohibitively expensive menswear.

In person, Ford is, as you would expect, immaculately turned out in an elegant, slim-fitting black suit. He’s an impossibly well-preserved 48-year-old with a face that looks like no expense has been spared on it. He is witty, open and immediately likeable. He is realistic about his status as a sex symbol and style icon. “I don’t really think about that stuff. I’m not foolish. I understand that my looks, or people’s perception of my looks, helps sell things. It helps me as a designer. We’re a visual culture. But I think of it as a tool to what I do, or I don’t think about it.”

Ford brings to his film-making debut the same obsessive attention to detail that has served him so well in his fashion career. The film itself is all about rediscovering the beauty in the details, as George, in preparing to die, starts really to see and appreciate the life around him. As he wakes from the coma of his bereavement, the colour of the film warms. Ford insisted that the film was shot on a now discontinued Kodak film stock in order to achieve just the right colour-saturated, slightly grainy look.

Although the spirit of the book remains intact, Ford added George’s planned suicide to give the film a dramatic impetus. For this, he drew inspiration from his own family history. “I want to spare the actual people who went through it. But yes, a very close member of my family went out and bought a gun. Very meticulous, laid everything out, a suit, a pair of cufflinks I had given him, paid all his bills. And then got into a sleeping bag and shot himself, because he didn’t want to make a mess.”

So what’s next for Tom Ford? He has often talked about wanting children. Is that still on the cards? “I recently realised that maybe it was better that I didn’t have them. I’m not sure I want to create new lives. I have a struggle with life. It’s tough. Creating another creature is a huge responsibility. Plus I might be too old now. I might be a little too set in my ways.”

What seems certain is that Ford will now pursue a parallel career as a film-maker. He is already writing a new project, “very different” from A Single Man. “I don’t want to talk about it yet. I want to live through the rest of this experience. I just finished editing two weeks ago, so it’s not out of my system yet.”

A Single Man will be shown on Oct 16 at 6pm, Vue5 and 6.15pm, Vue7, on Oct 17 at 4.15pm, NFT1 and Oct 19, 4.45pm, NFT1. The film will go on general release early next year

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