For decades, Jamie Lowther-Pinkerton knew there was a part of his mother’s extraordinary past that she simply would not discuss. Now, the former private secretary and mentor to Prince William and Prince Harry has revealed how his late mother, Sue Lowther-Pinkerton, secretly served with MI5 after a remarkable wartime life.
Lowther-Pinkerton served William, Harry and Catherine, then Duchess of Cambridge, from 2005 to 2013. He guided the princes through their early adult years, military careers and public duties, and remains an Extra Equerry. His son Billy was a page at William and Catherine’s 2011 wedding, and Lowther-Pinkerton is also godfather to Prince George.
The bond he built with both brothers during those years has taken on new weight given how differently their paths have unfolded since — a dynamic that resurfaced when reports emerged about King Charles’ outreach toward Prince Harry reportedly creating tension with Prince William.
Who Was Sue Lowther-Pinkerton? The MI5 Career Her Family Barely Knew About
Sue Lowther-Pinkerton, born Susan Kathleen Leslie-Smith on September 9, 1924, was raised on the North-West Frontier of what was then India, now Pakistan, as a “daughter of Empire.” She developed a rebellious streak early in life and was expelled from educational establishments, including a Swiss finishing school.
Her wartime story was already extraordinary before MI5 entered the picture.
While still underage for enlistment, Sue worked on NAAFI vans serving troops and painted white lines on roads. In 1942, she joined the Auxiliary Territorial Service (ATS), the women’s branch of the British Army.
She was posted to the Royal School of Artillery at Larkhill, where she drove gun limbers across firing ranges. The dangerous assignment earned her an extra four pence a day. She also worked as a motorcycle despatch rider.
After leaving the military in 1948, Sue moved into Army intelligence in Singapore. There, she handled secret communications connected to HMS Amethyst’s planned 1949 breakout from China’s Yangtze River.
Then came the chapter she would barely ever discuss.
| Year | Event | Official detail |
| 1924 | Sue Lowther-Pinkerton born | Susan Kathleen Leslie-Smith |
| 1942 | Joined ATS | Women’s branch of the British Army |
| 1948 | Left military service | Later worked in Army intelligence |
| 1951 | Joined MI5 | Worked at Leconfield House in Mayfair |
| 1956 | Left MI5 | Departed to start a family |
| 2023 | Died | December 24, aged 99 |
| 2026 | Son’s debut novel published | Beyond the Edge of Light |
Sue returned to Britain in 1951 and joined MI5, Britain’s domestic intelligence agency. She worked at Leconfield House in Mayfair until 1956, when she left to start a family.
But even after leaving the service, she maintained the silence expected of her generation. She refused to discuss even minor details of her intelligence work.
That instinct toward privacy is a world away from how royal-adjacent figures are discussed publicly today, where even secondhand claims can make headlines — as when a former nightclub friend of Prince Harry’s said Meghan had changed him.
The One Time Sue Broke Her Silence
The closest Lowther-Pinkerton came to hearing his mother discuss MI5 happened decades later while the family was watching a television documentary about the Cambridge spy ring.
The programme raised allegations that Sir Roger Hollis, MI5’s director general from 1956 to 1965, might have been a Soviet agent. The allegations were investigated but never proven.
Lowther-Pinkerton recalled:
“We were watching a documentary one afternoon about 30, 40 years ago… And up pops the documentary maker saying, ‘Well, it could be Sir Roger Hollis.’”
His mother responded immediately:
“Absolute nonsense. He was a total gentleman and a patriot.”
Lowther-Pinkerton said he and his sister looked at her “sideways as if she was completely mad.”
He was already in his mid-20s before he and his sister fully learned about their mother’s intelligence career. Even then, getting answers was nearly impossible because, as he explained, “she was of that generation who quite rightly just didn’t want to talk about it.”
That silence makes her eventual story even more striking.
Discretion of that kind stands in sharp contrast to how exposed royal circles can feel today, where even a public appearance draws scrutiny — as seen when Kate Middleton’s body language at Wimbledon 2026 sparked its own round of debate.
From MI5 Operative to Beloved Mother and Community Volunteer
Sue received 11 marriage proposals before accepting Anthony Hull Lowther-Pinkerton, known as “Rumpty.” He was described as a “great big Anglo-Irishman” and “everybody’s life and soul of the party.”
The couple settled in Suffolk and raised their children. At home, Lowther-Pinkerton remembered his mother as remarkably calm and unflappable.
“Nothing fazed her.”
Her ability to remain composed even extended to dealing with her husband’s bad moods. On one memorable occasion, she threw a roast potato down the dining table and hit him clean between the eyes.
Rather than causing a family meltdown, the incident ended with his father “literally crying with laughter within about 20 seconds.”
After leaving MI5, Sue spent nearly 50 years organising the annual Poppy Appeal. She also spent decades delivering Meals on Wheels to remote cottages and farmsteads.
Her life eventually became the inspiration for Missie, the central character in her son’s debut novel, Beyond the Edge of Light, a wartime love story published in 2026.
Lowther-Pinkerton has described the character as capturing “Mum in the wild, first half of her life,” including her looks, humour and quiet strength.
He read sections of the novel to his mother before her death on December 24, 2023, aged 99. According to Lowther-Pinkerton, she “chortled away.”
The book gave him a way to explore a part of his mother’s life that had remained largely inaccessible to him and his sister throughout their childhood.
While Lowther-Pinkerton has spent 2026 marking a quiet family milestone with his novel, the royals he once mentored have had milestones of their own make headlines, including when Prince William and Meghan Markle each landed 2026 Emmy nominations for very different projects.
Why Lowther-Pinkerton Remembers His Mother Alongside the Queen Mother
Lowther-Pinkerton has also reflected on similarities between Sue and the Queen Mother, whom he served as equerry.
He recalled shared qualities including sharp memories, humour and resilience shaped by wartime experiences. His distinguished military career with the Irish Guards and SAS, followed by his role as equerry to Queen Elizabeth the Queen Mother, eventually led him into the royal household, where he became a trusted figure around William and Harry.
His son Billy later served as a page at William and Catherine’s 2011 wedding, while Lowther-Pinkerton became Prince George’s godfather.
Yet behind that royal connection sits a family story that remained hidden for decades.
Sue’s MI5 career was never presented as a dramatic spy tale, and no operational details have been disclosed. Instead, the revelations paint a picture of a woman who moved from a rebellious childhood and dangerous wartime service into British intelligence, then quietly returned to family and community life.
Her son is now finally telling part of that story.
Her son is now finally telling part of that story — a far quieter reveal than the kind of royal-adjacent commentary that has circulated elsewhere, including claims from a former nightclub friend of Prince Harry’s who said Meghan had changed him.
Disclaimer: This article is based on publicly available interviews, obituaries and reporting from Fox News, The Telegraph, People, The Times, HELLO!, The Independent and other cited sources, researched and reviewed as of August 23, 2026. Details of Sue Lowther-Pinkerton’s MI5 service remain limited because of the confidential nature of intelligence work and her own lifelong discretion. No operational specifics have been disclosed. Statements attributed to Jamie Lowther-Pinkerton come primarily from his recent interviews. This article is not an official intelligence or royal record.
Sources
- Fox News — Prince William and Harry’s former royal mentor reveals mother’s secret MI5 past
- The Telegraph — Sue Lowther-Pinkerton obituary
- People — Jamie Lowther-Pinkerton’s debut novel and inspiration
- The Times — Interview with Jamie Lowther-Pinkerton
- HELLO! — Jamie Lowther-Pinkerton on royal life and his novel
- The Independent — Prince William and Harry royal family coverage
- Wikipedia — James Lowther-Pinkerton
Image Credit:
- Featured Image: John Pannell Wikimedia Commons (CC BY 2.0)
Leave a Reply