A paedophile prowls the streets in a white van, snatching children from outside their homes. Within minutes they’ve been beaten and stripped of their innocence. No, not a fevered urban legend – but the modus operandi of Britain’s vilest predator…

It happened in a flash in the ­sweltering heat of a lazy summer’s afternoon. As retired postmaster David Herkes mowed his front lawn in the quiet Scottish Borders village of Stow, something disturbing caught his eye.

A young schoolgirl was walking past a parked delivery van when she suddenly vanished. Mr Herkes, who had knelt to adjust the mower blade, happened to glance under the van at the moment the child’s feet seemed to lift up and disappear. There one minute, gone the next.

The van drove off before Mr Herkes could intervene, but he was alert enough to note down the number plate. Certain the girl was in terrible danger, the pensioner immediately ran to the local police station and within minutes a manhunt was in full swing.

Less than half an hour later, as Mr Herkes spoke to the local policeman, he was astonished to see the same van coming back along the road towards him, after it took a wrong turn.

Stepping bravely into its path, the officer forced the driver to stop. Opening the back of the van, he found the six-year-old girl hooded, bound and gagged with pieces of Elastoplast and stuffed inside a dirty old sleeping bag where, barely able to breathe, she would have surely suffocated.

With growing horror, the officer realised that the petrified child now clutched safely in his arms was his own daughter.

In the brief time she had been abducted, the traumatised youngster had been sexually assaulted, stripped of her innocence by a monster, who had already murdered and targeted a string of young girls in pursuit of his depraved pleasure.

There can be little doubt that the life of the policeman’s daughter would have ended at his hands too, but for the actions of a quick-thinking neighbour.

Instead, she would become the catalyst in a chain of remarkable circumstances that would finally lead to the capture of Scots serial killer Robert Black.

A white Datsun van similar to the one used by serial killer Robert Black

Even now, a decade after his death in prison, Black casts a long shadow as one of the country’s most notorious child killers.

But as a new Netflix documentary makes clear, no one had any idea of the true nature of the man arrested that hot July day in 1990.

By turns horrifying and compelling, the two-part series Child Snatcher: Manhunt charts how loner Black, a delivery driver in the 1980s, used his job as cover to abduct young girls across the UK, transporting and dumping their bodies hundreds of miles from home and exploiting gaps between fragmented police jurisdictions to evade capture for nearly a decade.

Focusing on his relentless pursuit by law enforcement officers – often grappling with their forces’ systemic failures – and highlighting the enduring trauma carried by grieving families, the programme builds into a stark and sobering examination of how one man’s evil exploited routine and distance to commit unthinkable acts.

Even now, it is impossible to say how many young lives he may have taken, but the names and now-familiar images of his known victims – Susan Maxwell, Caroline Hogg, Sarah Harper, Jennifer Cardy and Genette Tate – still fill every parent’s heart with dread.

In the end, it was blind luck that finally snared Black. After his arrest, Black seemed utterly unfazed. ‘What a day it’s been,’ he told police. ‘It was a rush of blood. I’ve always liked young girls since I was a young kid.’

Even after his capture it would be many years – in one case three decades – before Black, from Grangemouth, Stirlingshire, was brought to justice for his crimes.

Roger Orr, a retired detective chief superintendent and head of CID at Lothian and Borders Police in 1990, said it was clear from the paraphernalia left behind in the van that the Stow attack was not the perpetrator’s first.

‘Everything pointed to [him] travelling the length and breadth of the country and prepared to forcibly abduct children,’ he said. ‘And it was really quite menacing.’ Just how menacing would only become clear as Black’s unorthodox life unravelled.

He appeared at the High Court in Edinburgh in August 1990, within a month of the Stow attack, and pleaded guilty to charges of abduction and assault to the danger of life, receiving a life sentence. The court heard that his victim would have died of asphyxiation within an hour if she had not been discovered when she was.

As a new Netflix documentary makes clear, no one had any idea of the true nature of the man arrested that hot July day in 1990

With Black safely under lock and key, detectives from across the UK began to wonder about his involvement in unsolved cases on their patches.

There was nine-year-old Jennifer Cardy, excited to be out on her new bike in August, 1981, near her family home in Ballinderry, County Antrim. The bike was intended as a Christmas gift, but her father Andy persuaded his wife Pat to let the girl make use of it in the late summer to visit a friend’s house two miles up the road. She never arrived. Sexually assaulted and strangled, her body was dumped in a dam 16 miles away.

A year later, on July 30, 1982, 11-year-old Susan Maxwell disappeared while walking home from a tennis match in Coldstream, Berwickshire.

A white van had been seen in the area and, 13 days later, her body was found 264 miles away in Uttoxeter, Staffordshire, dumped in a lay-by. She, too, had been sexually assaulted and strangled. The following July, five-year-old Caroline Hogg disappeared from the beach opposite her home in the Edinburgh suburb of Portobello.

The seaside town was heaving with visitors but witnesses reported seeing a ‘scruffy man’ watching Caroline on the beach.

Another witness recalled seeing them talking on a bench before he led her by the hand into a fun fair, paying for her to ride on a carousel before leading her away.

Her naked body was found near a layby on the M1 in Twycross, Leicestershire, 310 miles from her home and just 39 miles from where Susan’s had been dumped.

Police quickly linked the murders of Susan and Caroline, believing the killer was someone who travelled long distances, possibly for work, in a van or covered vehicle.

Delivery firms from Scotland to the Midlands were asked to provide details of their drivers’ movements on the relevant dates.

Three forces – Lothian and Borders, Leicester and Staffordshire – were now working together on the case and Hector Clark, the Assistant Chief Constable of Northumbria who had worked on the Yorkshire Ripper case, was called in to lead the manhunt.

Five-year-old Caroline Hogg disappeared from the beach opposite her home in the Edinburgh suburb of Portobello in July 1983

In 1994, Black’s trial for the murders of Susan Maxwell, Caroline Hogg and Sarah Harper, took place at Newcastle Crown Court

For the first time a central computer was used to sift through the mountains of evidence from all over the country, and cross reference details.

Tragically, the search was still ongoing when Sarah Harper, ten, disappeared from the Leeds suburb of Morley, after popping to her local corner shop for bread on March 26, 1986.

In a distressing piece of archive footage, Sarah’s mother, Jackie, breaks down during a police appeal for help in catching her daughter’s killer.

‘He’s not going to stop at Sarah, is he?’ she said. ‘It’ll be somebody else’s child next.’

An extensive search of over 3,000 properties uncovered no clues and her partially clothed body was found 71 miles away in the River Trent, near Nottingham, almost a month later.

The operation was now the biggest serial killer investigation since the arrest of Yorkshire Ripper Peter Sutcliffe with more than 187,000 people interviewed, 60,000 formal written statements taken and over a quarter of a million vehicle records reviewed. In April 1988, it is thought Black struck again, attempting to abduct 15-year-old Teresa Thornhill, who managed to fight him off and run away.

Black’s interest in young girls is thought to have started when he was just 12, when he was accused of trying to rape a little girl.

Put into a Barnardo’s home by his unmarried mother, he molested a seven-year-old girl months after leaving care at 16.

Luring her into an abandoned air raid shelter on the pretext of showing her a box of kittens, he choked her to within an inch of her life. It was the start of a campaign of attacks during which he admitted ‘touching up’ more than 40 young girls over three years. It culminated in him being sent to Borstal in 1967 for indecent assault.

For years after, he operated under the radar until, after his arrest in 1990, police were provided with an unexpected breakthrough when his rented bedsit in London was searched.

While it failed to provide a single forensic link to any other murder, what it did yield was a pile of meticulously documented petrol receipts. Together with his employment records, they were used to track his movements.

‘He was a prolific hoarder of receipts which allowed us to put him at a particular place on a particular day and at a particular time.’ said Mr Orr.

Tom Wood, a former Deputy Chief Constable at Lothian and Borders, was an inspector with the Serious Crime Squad when he worked on the investigation.

He told the programme a compelling case was built against Black showing him ‘in all the right places at the right times’.

In 2011, 30 years after nine-year-old Jennifer Cardy was killed, Black was finally convicted of her murder

He said prosecutors were able to use a legal move known as ‘evidence of similar fact’ to show that three of the killings were carbon copies and almost certainly the work of one man.

‘It means we could use the example of the abduction in Stow to say, “Look, this is what he did, and here is Susie Maxwell; identical circumstances, and here is Caroline Hogg: identical circumstances, and here is Sarah Harper; identical circumstances.”

‘So you are saying to the jury, “How could it not be him?”’

While Jennifer Cardy’s murder was not linked at the time, her family suspected the same killer was responsible.

Her father, Andy, said: ‘We were told, in the early 1990s, that he was in the province on the day that she went missing. We knew then that Robert Black had killed our daughter.

‘It was only a matter of time, waiting and being patient knowing that he would come to trial at some stage in our province.’

In 1994, Black’s trial for the murders of Susan, Caroline and Sarah, took place at Newcastle Crown Court. It was a traumatic time for the families as they learned more about what their daughters went through in their final moments.

‘You can never bring Susie back, or Caroline back or Sarah. It destroys the families of these girls,’ said Mr Wood. ‘But it’s important that justice be done.’

When the jury began delivering their verdicts, everyone was on tenterhooks – because the cases had been linked, if one fell, they all fell.

In the end, Black was found unanimously guilty of all charges against him and ordered to serve ten life sentences. Quite what motivated his killing spree was never made clear.

Hector Clark, an old school policeman not given to hyperbole, branded Black a ‘vile, evil man’.

For detectives in Northern Ireland, there was yet more evil to uncover, but it needed patience and planning.

After nine years of sifting through mountains of evidence, lead detective Raymond Murray set up three interviews with Black in prison.

They used a deliberate tactic of using a female officer to lead the interview, hoping to coax Black into talking. It worked beyond their wildest expectations with the killer describing how he would abduct youngsters as he travelled around the country. Detectives suspected he was talking about actual crimes but avoided incriminating himself by claiming to be describing a fantasy.

But the detail of one fantasy was so startlingly similar to the events around Jennifer Cardy’s murder that officers believed they finally had enough to charge him.

In one recording, Black tells officers: ‘I’m not exactly proud of the way I feel towards young girls.

‘There’s a part of me that knows I’m wrong, that knows it’s wrong, that I shouldn’t be doing things like that, I shouldn’t even be thinking things like that.

‘But there’s the other part that says, “You like it, go on”.’

Not so ashamed to ever make himself stop.

In 2011, 30 years after Jennifer was killed, the case finally came before Armagh County Court and Black, who was already serving a minimum of 35 years, was finally convicted of Jennifer’s murder.

He is suspected of murdering many more between 1969 and 1990, including 13-year-old papergirl Genette Tate, who disappeared in 1978, and numerous children in Ireland, the Netherlands, West Germany and France.

Police were days away from charging him with Genette’s death when Black died of a heart attack aged 65 in Maghaberry Prison in Northern Ireland, on January 12, 2016.

His funeral was a basic cremation said to cost £1,000 and his ashes were disposed of at sea after no one came forward to claim them.

The memories of his young victims are cherished to this day by their loved ones.

Robert Black will be mourned by no one.

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