Piecing together the documents in the envelope, it transpired that Sandra Rivett was Berriman’s birth mother. “I remember it was difficult to breathe,” the 57-year-old says now of the moment of his bombshell discovery. “It was horrendous.”
Richard John Bingham, the 7th Earl of Lucan, vanished after Rivett’s murder at the Belgravia house he owned on 7 November 1974, in what police believed at the time (and an inquest later declared) was a case of mistaken identity, his intended target being his estranged wife Veronica, with whom he was engaged in a vicious custody battle.
Rivett had been bludgeoned to death, and while Lucan’s blood-stained car was later found abandoned in Newhaven, East Sussex, he was never traced, despite numerous reported sightings around the world.
Lord Lucan’s family maintained he had subsequently killed himself. He was formally declared dead by the UK’s High Court in February 2016. But father-of-two Berriman, from Hampshire, is convinced that Lord Lucan, who would be 90 in December, is still alive.
His journey to discover the truth and try and unearth new evidence of Lord Lucan’s whereabouts – working with investigative journalist Glen Campbell – features in a compelling three-part BBC documentary that takes the pair from South Africa to Australia.
Berriman’s mission to find out what really happened began in earnest when, in 2012, Scotland Yard allowed him to see harrowing photographs of the crime scene.
The legacy of seeing those images has been visceral and long-lasting. “I was on antidepressants for two and a bit years… Because there’s my mother dead, and somebody’s got away with it,” he says. He pauses. “Even now, talking about it, I can still see those pictures.”
Berriman was born when Rivett (who became pregnant with a married man) was just 21, and given up for adoption. He enjoyed a happy, “normal” childhood with his adoptive parents Ian and Audrey, and while he was told at the age of 10 that he was adopted, he had little interest in his birth parents. “As I got older, Mum would try to push this brown envelope on me, but I said I wasn’t interested in finding out about my real parents – until one of my adoptive parents passed away,” he recalls.
Even then, it took three years after Audrey’s death from cancer in 2004 for Berriman – by then approaching 40 – to take the envelope out of what had been her bedside drawer. “Perhaps it was a milestone birthday,” he says. “I felt the time was right.”
Nothing could have prepared him for what was inside, and it sparked an intense desire to find out more about the young woman who had given birth to him. “Of course, there wasn’t a great deal of information about her out there, because all along Sandra has been the forgotten victim; everything’s always been about Lord Lucan,” he says. “It’s one of the reasons I decided to embark on this mission. I’ve done it for my mother. Because who else was going to?”
As he immersed himself in trying to find out more, Berriman says he was “stumped” at the notion that Lucan – about whom he admits nurturing intense feelings of “hatred and anger” for many years – had simply disappeared off the face of the Earth.
“The fact was, there was no proof that he was dead,” he says. “And if he wasn’t, I wanted to see him brought to justice.”
His partner, Kim, and his now grown-up children Oliver and Melissa from a previous marriage, have also been affected by a quest that Berriman, a builder by trade, admits has dominated his waking hours for years.
“It did take over,” he says. “It was 24/7 and it was everything that we used to talk about. And I could see Kim was fed up with it, but it didn’t stop me. But she stuck by me, and the kids, too.”
He admits there have been times when he regrets opening that brown envelope 17 years ago. “It’s caused a lot of anguish, but deep down, I don’t [regret it]. Because even after all the upset it’s about justice,” he says.
“People talk about this big mystery, but that didn’t matter to me. All that matters is the mum I never knew.”
Lucan will start airing at 9pm on Wednesday 6th November on BBC Two.
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