Exposing the follies and childish foibles of our rulers takes up much of Simon Carr’s time these days. As a political columnist with the Independent he earned the ultimate badge of honour: being described as “the most vicious sketch writer working in Britain today” by Tony Blair, no less.

But his own chaotic life as a single father in charge of two boys is now being laid bare in the remarkable film The Boys Are Back, which charts what happened when Carr’s family was shattered by the death of his wife, Susie, from cancer.

“Did mummy die last night?” he was asked 15 years ago by his five-year-old son Alexander, a moment forever burned into the writer’s memory.

Recently, he found himself hearing that same heartbreaking question, only this time he was sitting in a cinema, watching the heart-throb actor Clive Owen recreating that unbearable scene for the world to see.

Carr, 57, who lives in North Oxford, is, of course, flattered to see his younger self portrayed on the big screen by Owen, who has previously starred as King Arthur and Sir Walter Raleigh, and played male lead to the likes of Julia Roberts, Angelina Jolie and Catherine Zeta-Jones.

But he admits to having watched the film through salty tears, while for his youngest son the experience turned out to be harrowing.

“Not to put too fine a point on it,” reflects Carr, “it turned us all inside out.”

The Boys Are Back may be about a family’s tragic loss, yet it is also an uplifting and, yes, frequently hilarious account of Carr’s efforts to bring up two boys without a mother, unaided, on the other side of the world, in a home bereft of any female influence whatsoever.

The journey from shell-shocked widower to hands-on father trying to bring his family back from the brink took place in New Zealand, where he had gone to live with Susie and their baby son after she became ill.

The film is based on Carr’s book The Boys Are Back in Town, published almost a decade ago, which gives a compelling account of life as a single parent having to make up the rules as he went along in an all-male household, where he could give free rein to what he calls his “free-range” approach to parenting.

He offers a glimpse of just what it was like, early in his memoir.

“We are a father and two sons living without women. We are like an experiment in a satellite, free of normal earthly influences (like guilt and bleach and sock drawers). We’ve been way off the norm, well outside the boundaries, so we know all about the hog-heaven theory of childhood.

“We are very widely experienced in the world where boys sit on the carpet gaping at the television like cultish prisoners. We’ve known Sunday nights when you can’t see the carpet for video boxes, takeaway packaging, clothes, plastic games, cats, goggles, guns, popcorn, plates, cutlery, papers, paintbrushes, cushions, soft toys, comics, newspapers, dart launchers, picture books, Lego and game CDs called Living Dead, Krypt, Resident Evil 2, where innocent bystanders are eaten alive by hungry zombies.

“We’ve lived for years now in a whole new, all-male institution. Given its inadequacies as a child-rearing unit, I like it.”

This novel approach was based on an eccentric philosophy that he developed to child-rearing that can be summed up as, “Just say ‘yes’”. It meant resisting the instinct of saying ‘you can’t do that, you might hurt yourself’.

And it meant allowing his sons to ride around the house on their bicycles or to leap into a full bath from a window sill.

In the film we see the young Alexander sitting on the bonnet of his father’s car as they drive along the beach at 30mph with spray flying everywhere — but surely not in real life?

“Well, yes actually,” chuckles Carr, although he insists that in real life the car was moving only at jogging pace.

But Alexander used to sit on his windscreen, hanging on to the wipers, feet on the bonnet, and it wasn’t a bit unusual for the Carr family.

“In my defence I say that we had to make it up as we went along. There weren’t any guidelines or role models for our situation.”

It seems father and sons have all come through the experiment in reasonable shape and, miraculously some might say, without serious injury.

He eventually decided to return to England, with the boys completing their schooling in Oxford, where they set up home in Southmoor Road, after Carr became unhappy with the quality of education in New Zealand — the final straw being when Macbeth GCSE coursework was to build a medieval castle out of cardboard.

Alexander, 20, who, like his brother, went to d’Overbroecks College in Oxford, is now studying at Brighton University, while Hugo, 26, the son from Carr’s previous marriage who completed the happy trio when he came to live with them at the age of 11, is now doing a PhD at Imperial College, London.

As for father, who was a student at Brasenose College (he arrived at Oxford University a year before Tony Blair), he is now married to Jose Strawson, the director of the linguistic institute, Alliance Francaise, based in Polstead Road. They were wed in July.

When we met at the institute, the chic and beautifully designed surroundings could not have been in starker contrast to the world of uncollected washing, freezers full of rotten food and semi-feral conditions that he once knew, and even relished, particularly on seeing the appalled faces of visiting mothers.

No doubt the New Zealand mothers went even more pale when they heard about the riding on cars, swimming in the night-time surf, screaming in the park with torches, the arc of the 40 ft swing and the terrifying Carr family game called ‘Come Here Little Boy’.

But there was always one big rule.

“They had to do everything I told them to,” says Carr. “But given that I told them to do about a third of what two parents would have done, the deal was good enough to work.”

He originally planned to set out the story of his experiment in a series of articles highlighting the significance of gender when it comes to parenting.

“I wanted to base it on the idea that fathers care less about their children. It’s not that they couldn’t care less. It’s just that they do not care as much as mothers do. When a baby is born, dads welcome a little stranger who has arrived. But for the mother there is a sense of loss. A mother’s embrace is actually reclaiming a part of herself. And she knows how vulnerable they are.”

So, he argues, women overestimate risk, men underestimate it, with mothers also more interested in details and routine.

The feature idea was taken up by his old friend Tina Brown, former editor of Tatler and Vanity Fair, who was then running the short-lived Talk magazine in New York.

Looking through the notes he had carefully made throughout his children’s boyhoods — something he strongly recommends (“They say such marvellous things, but you forget.”) — he decided to write a full-scale memoir.

He sent a copy of his book, which has just been republished by Arrow, to Peter Bennett-Jones, the Oxford-based film producer, whose films include Billy Elliot.

“It was a bit presumptuous,” said Carr. “He gave it to his wife, Ali, who said, ‘you’ve got to make it into a film’.”

Over pints in their local, The Rose & Crown, in North Parade, the project was developed, but it has taken more than eight years to complete.

The film ended up being shot in South Australia, rather than New Zealand, and its central figure is a sports journalist.

While in New Zealand, Carr did indeed ghost-write a series of bestselling sports books, including one for the former All Blacks rugby captain David Kirk (a former Oxford man himself), he also found time to write speeches for the New Zealand Prime Minister and to help form a new political party.

Carr says he was greatly moved by Clive Owen’s performance in the film.

“He was fantastic. He gives a really contained and unsentimental performance.”

Seeing his character played by someone else was, however, peculiar, not least when it’s a Hollywood hunk.

In return, Owen was equally impressed with the writer he portrays.

“Every time I read the script I was practically in tears,” said the Hollywood actor, relishing the break from romantic comedies and action thrillers to work entirely with two child actors. “The idea of losing a partner and being left with the children is devastating. Grief is complicated. Parenting is complicated.”

But he said he plays the father as a fallible character.

“He’s not naturally very good at family life and this is a crazy, upside-down, volatile time for him. There are moments when things get really out of hand and he does make some big mistakes. But, ultimately, you see that he’s trying to do the right thing in his own way.”

The Closer star said he found meeting Simon Carr an emotionally-charged experience.

“It was a very profound day when he turned up on the set right towards the end. When you’ve done a film like that, it’s part of someone’s life. It’s a very important passage of all three of those guys’ lives.”

Interestingly, Carr, the son of a Foreign Office diplomat, was born in India, where the rules were clearly defined by his mother. She certainly would not have tolerated running such a loose ship.

“Fewer rules, but bigger ones, that was my formula,” said Carr. “More rules would have meant more crime. The fewer the rules we had, the nicer we were to each other. It was also a coping strategy. I just did not have the energy to enforce rules.”

On the week The Boys Are Back opened, he has been busily covering the Chilcot Inquiry into the invasion of Iraq. His wild days with the boys in New Zealand are long gone, but seeing the film has been deeply cathartic for him, helping him, he says, to better understand the impact of his late wife’s death.

“And, of course, the Clive Owen thing has boosted my reputation,” he grins. “It’s what I look like on the inside.”