Three events in my life converged in February 1985. Firstly, the eldest of my five children was born, late but unscathed, in Greenwich hospital; secondly, I performed in a production of Tom and Viv on Broadway, my first seminal experience of New York; and thirdly, the American actor, Ed Herrmann, playing T. S. Eliot in that production, presented me with Angus Wilson’s biography of Rudyard Kipling. Inside the front cover, Ed wrote: “Here’s hoping your Rudyard comes to pass.” As I flicked through the biography’s illustrations, I had the uncanny experience of staring at myself. My physical resemblance to Rudyard was unnerving – huge eyebrows, moustache, baldness, myopia – only the colour of the eyes was different. So, sitting in my apartment in West 87th Street, wrapped in an overcoat to ward off one of the coldest New York winters, I started to read The Strange Ride of Rudyard Kipling, and so began a journey that has taken 22 years and five months to complete. A journey that has led me to the caravan in which I am sitting now, in a field 100 miles from Dublin on the film set of My Boy Jack.

Initially, I read Wilson’s portrait of Rudyard with the slightly grimy motives of the actor on the make – here was a part I could play! But, as I delved deeper into his life, I discovered that, though I resembled Rudyard physically, his personality was extraordinarily similar to my father’s. This discovery was crucial. Writing My Boy Jack, both the stage play and the screenplay, would transcend pure actor’s greed and become something intensely personal. If My Boy Jack works on any level, it is because it is a hybrid of the Kipling family’s experience and my own family’s experience. My portrayal of Kipling is an unashamed mix of my father and Rudyard.

My father was a vocational soldier and an army officer for 20 years.

When he retired from the Army in his forties, bored by the inertia of postwar army life, he went on to run the Hayward Art Gallery for ten years from its opening in 1966. He was an extraordinary mix of artistic sensitivity and old-fashioned Victorian values. It was this paradoxical combination that I immediately recognised in Rudyard – the magical, inventive father, creator of The Jungle Book and Just So Stories, clashing with the tyrannical apologist for the British Empire. How did these apparently incompatible extremes sit within one personality? Not comfortably, I suspect, for Rudyard or my father, but it is a fascinating mix to observe.

My Boy Jack is the story of Rudyard’s “inadvertent complicity” in his son’s death. Complicity is a provocative word and needs clarification. Rudyard’s son John (known as Jack) was 17 years and a few days old when Great Britain declared war on Germany in September 1914. Like the majority of his peers at the beginning of the First World War, Jack was determined to fight for King and country, but, like his father, he was profoundly myopic, so shortsighted that the Army and the Navy rejected him out of hand as “a danger to himself and to his men” – and this at a time when the country was desperate for volunteers. But Rudyard was undeterred and utterly determined that his son should fight, despite his impaired vision, for the values that he, Rudyard, so publicly espoused. It is impossible to overemphasise the writer’s status in 1914. He was the voice of the Empire, he had the ear of the King and the Prime Minister, and was as globally popular (and, incidentally, as wealthy) as J. K. Rowling is today. Using this massive influence, he managed to persuade his friend and hero Field Marshal Lord Roberts to arrange a commission for Jack in the Irish Guards. And so, in August 1915, Second Lieutenant John “Jack” Kipling crossed the Channel bound for the Western Front. He took with him a spare pair of specs and a letter from his father giving him permission to fight under the age of 18. On September 27, 1915, in the Battle of Loos, Jack was killed on the first day of his first action, in torrential rain. Anyone who has worn spectacles in heavy rain will know that Jack will have been unable to see a thing.

The effect on Rudyard was immediate and irrevocable. Guilt, remorse and grief flooded his writing and physical illness plagued him. He sought atonement by writing a 700-page history of his son’s regiment, and by pouring his energies into the War Graves Commission. In 1917 he wrote a simple couplet, the universal voice of every teenage son killed in the Great War: “If any question why we died/ Tell them, because our fathers lied.” It would be impossible to condense Rudyard’s sense of guilt more succinctly.

I am not a pacifist. Some wars I believe are just – the need to stop Hitler was indisputably necessary – but, as an atheist, what I cannot bear is that every death in war consigns a human being to oblivion. And every individual death in Iraq, Afghanistan, or the Battle of Loos in 1915, sets off a chain reaction of connected lives damaged and, in some cases, destroyed – families and friends who struggle for the rest of their lives to come to terms with that one single loss. Yet on the morning of September 27, 1915, Jack Kipling’s last morning, 7,500 British soldiers died, each producing his own chain reaction of collateral emotional damage.

My own family has had its share of premature death. My sister died of a brain haemorrhage when she was 22, my wife Julia had a full-term still birth, Julia’s sisters lost their husbands at 47 and 52. I have seen at first hand the jagged, unpredictable nature of grief and bereavement within a family. Interestingly, at the very moment when one would expect indissoluble unity, the reverse can be true. How often does one hear in a notorious murder case that the parents of the victim have cracked under the strain and separated? Despite losing two of their three children under the age of 19, Rudyard Kipling and his wife Carrie’s marriage survived. Their interdependency and mutual devotion outweighed the strain.

Apart from describing Jack’s journey, the film My Boy Jack focuses on the family, on what it means and feels like to lose a brother or a son, the cost to the survivors. It is a story of specificity, about Rudyard Kipling, a superstar of his generation, but I hope it is also a universal story, which can speak to any family, anywhere. Remembrance Sunday rightly focuses on the men who sacrificed their lives, but it is also worth remembering the cost to the families who struggle to come to terms with the loss of a father, brother or son.

My Boy Jack, Sun, ITV1, 9pm

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