Rachel Nickell was walking her dog Molly with her two-year-old son Alex when she was brutally stabbed to death on Wimbledon Common on 15 July 1992.

An unknown man approached from behind, pushed Alex aside, stabbed Rachel 49 times and sexually assaulted her.

Her toddler was the only witness in a case that truly shook the nation.

The little boy watched the assailant wash his hands in a nearby stream before leaving, then clung to his 23-year-old mother’s body until they were found.

Officers who arrived at the scene had to prise him away.

‘It was an incredibly high-profile case. A mother and her young child walking on Wimbledon Common in the middle of the day – you don’t expect that sort of thing to happen. There was huge public sympathy,’ forensic scientist Angela Gallop tells Metro.

Police quickly sealed off Wimbledon Common and began one of the largest murder investigations the Metropolitan Police had ever seen. Three incident rooms were set up, while helicopters, mounted officers and forensic teams combed the area.

Witness appeals went out almost immediately through television bulletins and newspapers, triggering a media frenzy. The nation was shocked by the brutality of the broad daylight attack.

In a race against time to find the killer, detectives and psychologists worked with Alex for months, trying to glean information as his anxious father André Hanscombe watched on, fearful of the long-term effects of repeated questioning.

Behind the scenes, the heartbroken dad was desperately trying to keep life as ‘normal’ as possible for his traumatised son.

‘Literally hours after the event, I kept as close to the routine Rachel and Alex shared together as I could,’ André explains, as he shares never-before-seen pictures of Rachel and Alex.

‘That would have been important to her and was important to me. My aim was building a routine he could rely on, from having the same bowl of cereal for breakfast, having a walk, and doing ordinary things – even going back to parks that looked almost identical to the place where the attack took place.’

Now 36, Alex adds: ‘But at the same time, in many ways that was impossible, we couldn’t return to our home, which was surrounded by reporters and because there was a killer on the loose.

‘We were staying temporarily with family and friends, until ultimately we were tracked down and moved to another country, where we lived in rented accommodation, ready to pack up and move on in a moment’s notice.’

With DNA testing at the time fruitless, police struggled to find concrete leads.

In September 1992, Colin Stagg was arrested after viewers of Crimewatch said he resembled the photofit of the killer. He was released but arrested again in 1993 and later charged with Rachel’s murder. After spending over a year in custody, the case collapsed at the Old Bailey in 1994.

Years passed with no answers. Meanwhile, there was more violence.

Police were investigating a series of sexual attacks that became known as the Green Chain rapes, carried out across parks and open spaces in south-east London between 1989 and 1993. 

Then, in November 1993, Samantha Bissett, 27, and her four-year-old daughter Jazmine were found murdered at their home in Plumstead, south London.

It was one of the most shocking cases detectives had ever encountered.

Retired Detective Sergeant Roger Boydell-Smith, the exhibits officer at the time, remembers the moment he entered the flat.

‘My detective superintendent put his arm around me and said, “Roge, brace yourself, son, because this is the worst one I’ve ever seen”.’

Recalling what he saw for Netflix documentary The Murder of Rachel Nickell, Roger says: ‘When we walked in, it became apparent that Samantha had been possibly stabbed to death in the hallway, dragged through to the living room and placed on a large cushion in a star formation, and she’d been mutilated.’

The detectives then found four-year-old Jazmine dead in her bed beneath a duvet, suffocated and sexually assaulted.

‘I’ve dealt with lots of murders in my career. This one was horrific. It does affect you emotionally,’ Roger tells Metro.

The police took hundreds of fingerprints but were unable to find any that could not be eliminated as belonging to family or visitors. There was no DNA or other clues.

They soon drew potential links with Rachel Nickell’s murder 16 months earlier – young mothers, extreme violence, multiple stab wounds while children present – but the Nickell investigation team rejected the idea, says Roger.

‘It’s extremely rare that strangers attack members of the public. Children being present is even rarer. He’s probably done something similar before.

‘We couldn’t fathom out how, within a gap of 16 months between the Wimbledon common murder and the Plumstead murder, two different people could carry out such ferocious, audacious crimes. So was it possible that the same person committed both?’

At the time, Colin Stagg was still awaiting trial and the investigation team were convinced they had man who killed Rachel.

‘For us to suggest that they might have got the wrong man didn’t go down very well,’ remembers Roger.

Prior to the murders of Samantha and Jazmine, an artist’s impression of the Green Chain rapist was distributed widely across Southeast London’s public places and police stations.

A member of the public reported a man called Robert Napper and the police went to visit him at his Plumstead bedsit.

He was cooperative and gave his details, but failed to attend a later appointment to provide samples. Napper was eventually ruled out, partly because he was thought to be taller than the assailant.

‘That was a catastrophic decision because he went on then to murder the Bissetts,’ says Roger. ‘He could have been caught quite easily. The officers involved will have to live with that for the rest of their lives.’

When evidence from Samantha’s flat was later re-examined it revealed a shocking discovery – one of the prints inside was Napper’s.

He was arrested and inside his tiny bedsit, detectives found a padlocked red toolbox containing knives, a book about methods of strangulation and an map of London what was covered in markings and doodles – one of which was very near the spot where Rachel was killed.

Napper was later convicted of the killings of Samantha and Jazmine on the grounds of diminished responsibility and detained indefinitely at Broadmoor Hospital in 1995. 

Tragically, one woman who never saw justice served was Samantha Bissett’s mother.

Maggie Morrison, 53, collapsed at her home in Stonehaven, Aberdeenshire, 48 hours before Napper was convicted. Her husband Jack said she’d died of a broken heart.

‘Samantha was an only child, and her mother, Margaret, never recovered from the loss of her only grandchild and her only daughter,’ says Roger.

‘It’s just very, very sad case. So many lives were ruined.’

Following Napper’s conviction, the independent police watchdog found a “catalogue of errors” in the investigations, concluding missed opportunities that allowed the killer to remain free. 

Meanwhile, Rachel’s murder remained unsolved and Alex and André – now living in France to keep Alex safe while the killer remained loose – started to accept that they would never get answers.

‘I had some familiarity with France but moving there meant losing our home, leaving behind family and friends – in short, everything that was our life. It was a turning point decision made from the heart,’ remembers André.

‘Rachel and I had dreams about moving to France and having more children together. She was a real nature lover, so [for me and Alex] to be out there enjoying the changing seasons, being able to walk in bare feet and pick the fruit from the trees – she would have loved to share those moments with us.

‘It was idyllic – or, it would have been idyllic in any other circumstances, which was unbearably bittersweet.’

In 2002, forensic scientist Angela Gallop, who worked on high profile cases including James Bulger, Princess Diana and George Harrison, was asked to review the evidence in Rachel’s case.

It was painstaking work. Evidence had to be re-analysed in conditions that eliminated any risk of contamination.

‘We thought – right, we’ve got to make our technique more sensitive. We need to do something slightly different,’ she tells Metro. It took two years, but they ended up with a DNA profile that they could feed it into the database – and matched with Robert Napper.

‘We went back to the crime scene, looked at all the samples and items that were collected, and noticed that there was a cast of a footwear mark on the muddy ground,’ recalls Angela. ‘And we thought – that’s interesting.’

The cast mark was smaller than Napper’s shoe that had been kept in evidence. So the team analysed the boggy ground in the glade where Rachel’s body had been found.

‘We discovered that if you press foot down on the on the ground, and then lift the shoe, the mud closes around it. So when you then cast the mark, it will be smaller than the shoe that made it.’

They also found paint flakes in Alex’s hair that matched paint from a toolbox containing knives and other weapons that had been found in Napper’s flat.

It was enough to see the killer finally brought to justice for Rachel’s murder.

In January 2016, Robert Napper, then 42, pleaded guilty at the Old Bailey to the manslaughter Rachel Nickell. He remains in the high-security psychiatric facility Broadmoor Hospital today.

34 years on from Rachel’s murder, Netflix are releasing two titles based on her story – the three-part drama series The Witness, starring Kerry Godliman and Claire Rushbrook, and a documentary, The Murder of Rachel Nickell.

Alex and André have been involved in both, with the dramatisation being based on Alex’s memoir, Letting Go.

Talking about his early childhood, Alex says: ‘I have memories of both my parents together, some very early memories. I was blessed to have two incredibly loving parents who cared deeply about me, went the extra mile for me and were willing to suffer for me.

‘My mother suffered to protect me in her last moments, and my father suffered to protect me from there. Our relationship hasn’t always been easy, but nothing has ever been able to take away the love I have for my father, and I believe nothing ever will.’

André adds: ‘ People saw those headlines about a tragedy, a small nearly-three-year-old child, what he saw that day, and headlines saying he may never talk again from the trauma he suffered.

‘I know that the most important thing to Rachel would be his recovery, and of course it was the most important thing to me as well, having suffered abuse as a small child.

‘Alex always had a huge appetite for life, and I want people to know that, and to know that he’s doing well.’

However, Alex believes his mum never got the justice she deserved.

‘For 33 years, the police have washed their hands of their responsibility and their failure to do their job to serve and protect,’ he says. ‘They failed to take the killer off the street years before the attack on my mother and me.’

A Met Police spokesperson told Metro:

‘We are deeply sorry for the failings in the investigation into Rachel Nickell’s death.

‘We accept that we should have done more to identify Robert Napper as a suspect, which could have prevented a number of serious attacks by him.

‘Since Rachel’s murder, the Met has overhauled how it investigates homicides, including better training of detectives, new forensics techniques and closer work with the Crown Prosecution Service.’

Both the drama series The Witness and documentary The Murder of Rachel Nickell will be available to watch on Netflix from Thursday, June 4.

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