In the early evening of 5 January 2023, police were called to a burning car abandoned on the hard shoulder of the M61, near Bolton. Inside the wreckage, officers discovered £2,000 in cash, 34 cheap mobile phones, and a woman’s passport.

A placenta wrapped in a towel was found on the back seat. It revealed to police the existence of a newborn baby.

The owner of the passport and her partner, it emerged, were well known to social services. A nationwide search was launched to find them, which quickly became front-page news.

But for the next two months, through a bitterly cold winter, the couple went to exceptional lengths to avoid being caught. Despite having access to plenty of money, they lived rough in a cheap tent and scavenged in bins.

When they were eventually arrested at the end of February, their baby was no longer with them - and they refused to tell police where she was.

The pair had been desperately trying to stay out of reach of authorities because this was not their first child. They had four others - all of whom had been taken into care.

Within days, police made a grim discovery in a shed in Brighton, close to where the man and woman had been arrested. Inside a Lidl "bag for life", covered in soil and rubbish, the body of a baby girl - just a few weeks old and wrapped in a pink sheet - was found.

The BBC has been investigating the lives of Constance Marten and Mark Gordon, and the events that led to the death of their fifth child, Victoria.

Marten is from a wealthy family with strong connections to royalty - she told friends she played with princes William and Harry as a child. Gordon is the son of a nurse who emigrated to the UK from the Caribbean.

As teenagers, one of them travelled to Nigeria to join a secretive evangelical church, while the other was sent to a Florida prison for rape.

The story of how Constance Marten and Mark Gordon’s lives became entwined, then descended into chaos, and ultimately led to a tragedy, begins soon after World War Two.

In late November 1949, a dazzling society wedding attended by the King and Queen took place at St James’s Palace.

The bride was the Queen’s goddaughter, a glamorous heiress who owned one of England’s most beautiful country homes, Crichel House.

A decade later, she gave birth to a son, Napier. Educated at Eton College, he served as a Page of Honour to Queen Elizabeth II - a distinction granted to the teenage sons of members of the nobility.

Napier married a socialite named Virginie Camu in 1986, and subsequently fathered three children. The eldest, a daughter named Constance, was born in May 1987 - and soon became known to almost everyone by the nickname "Toots".

Mark Gordon’s mother, Sylvia, came to the UK as one of the Windrush generation. She married Luckel Satchell, also from Jamaica, with whom she had four children. But her marriage was over by the time she was pregnant with Gordon, her fifth child, who she gave birth to in 1974.

Karen Satchell, Gordon’s sister, told the BBC her younger brother was a shy boy who could be a "little mischievous".

"I’ve never seen him have a fight," she says. "Nothing at all, never."

While Gordon was still young, Sylvia left her job as a nurse at the Chrysler car factory in the Midlands, and moved to the US, eventually settling in Florida. It was here, aged 14, while growing up not far from downtown Miami, that Gordon, pictured below, committed a brutal crime.

US court papers show in the early hours of an April morning in 1989, he broke into his 30-year-old neighbour’s home, armed with a pair of garden shears and a kitchen knife.

Dressed in black, with a stocking mask pulled over his face, the court heard Gordon told the woman not to scream or he would kill her son and daughter, who were sleeping in the room next door. For the next four and a half hours, he raped her at knifepoint.

"I was told to say goodbye to my children because this was the day I was going to die," the victim told the courthouse during sentencing.

In the days that followed the attack, a police sheriff patrolling the neighbourhood found a nylon stocking with eye and nose holes outside Gordon’s house and he was taken in for questioning.

Gordon initially pleaded guilty, but later withdrew his plea and stood trial.

At his sentencing hearing in 1990, the woman he had raped implored the judge to impose a harsh term on Gordon, who was now aged 15.

"I ask you to make sure this man does not have the opportunity to destroy any more lives," she said. "Show him no mercy."

Mark Gordon was sentenced to 40 years in prison.

While Gordon was behind bars in Florida, Marten - 13 years his junior - was growing up in Dorset.

She attended St Mary’s, Shaftesbury, a private girls’ school where she had a reputation for being a bit of a rebel. At the age of around seven, her parents separated. Her father reportedly left his family for a journey of spiritual discovery in Australia, while Marten’s mother was pregnant with her fourth child. She later remarried.

The BBC has learned that after finishing school in 2006, Marten and her mother flew to Nigeria, to visit a church called the Synagogue, Church of All Nations (Scoan) in Lagos.

Marten’s mother, by now known as Virginie De Selliers, then returned to the UK, while her daughter stayed behind to become a disciple there.

A BBC Africa Eye investigation found evidence of widespread abuse and torture at Scoan under TB Joshua’s leadership, including allegations of rape by Joshua himself and forced abortions, spanning almost 20 years. The preacher died in 2021.

Several former disciples told the BBC they were physically and sexually abused by Joshua, pictured below in 2014, whom they called "Daddy". The BBC has no reason to believe Marten - who was 19 at the time - was subjected to any abuse there.

While at Scoan, Marten got to know a disciple called Angie, who has since left the church.

She remembers Marten as "bright, witty, compassionate, funny, kind, and very independent".

Angie says all female disciples - including Marten - lived in the same dormitory. Asked to denounce each other in humiliating public meetings, they often went hungry and were deprived of sleep.

"It's very hard to explain how scary that place was," says Angie, who spent 10 years at the church while headed by Joshua. "It was a place of torture and psychological abuse, physical abuse, spiritual abuse, and sexual abuse."

The BBC approached Virginie de Selliers for comment, but she did not respond.

After four months, Marten was thrown out of Scoan and returned to the UK, where she enrolled in Arabic and Middle Eastern Studies at Leeds University and spent a year in Cairo.

While still a student, Tatler magazine featured 21-year-old Marten as its "babe of the month". In the January 2009 article, she describes a party thrown by a viscount as like "a debauched feast from ancient Greece", and says she plans to get a tattoo of a tortoise.

Six years after leaving Lagos, Marten reached out to her old friend Angie on Facebook. In messages seen by the BBC, she talks about her time in TB Joshua’s church.

"I haven't spoken to anyone about what happened at the synagogue," she writes in October 2012. She never wanted to believe Scoan was a cult, she continues.

"It’s taken me years to ‘get back to normal."

Scoan did not respond to allegations in the BBC Africa Eye investigation but said previous claims have been unfounded and: "Making unfounded allegations against Prophet TB Joshua is not a new occurrence… None of the allegations was ever substantiated."

After university, Marten worked as a researcher at the Al Jazeera news channel and tried to make a documentary about TB Joshua. But by 2015, she had left journalism and was training to become an actress.

Ade Oshineye studied at the East 15 Acting School alongside her.

"She's one of those people that stands out in the crowd," Ade says. "She's a striking person."

Another friend of Marten’s at the time was SHNO - now an actress and recording artist.

"She was just such a cool person," SHNO says. "She was quite special - she would always see the best in people."

Marten told her drama school friends she was the black sheep of her family. She was estranged from her parents, she said, but still good friends with one of her brothers. SHNO also remembers Marten talking about aspects of her childhood that revealed her privileged background.

“She told me she used to play with Prince Harry and Prince William,” SHNO says. “She said it like it was really normal.”

Both Ade and SHNO assumed a successful acting career lay ahead for Marten.

“She was just so talented. I feel like she could just walk straight into Downton Abbey because she has that aura, the presence, the voice.”

But in early 2016, Marten vanished. She no longer came to classes, didn’t return calls, and nobody could reach her on social media.

"It was a massive jump from being very sociable to suddenly you can't get in contact with her," Ade says.

"She’d just gone without a trace."

Gordon had been released from prison in early 2010 after serving 20 years. He was deported back to the UK, where he was put on the sex offenders’ register.

His sister, Karen Satchell, says he has always been guarded about his time in jail.

"Still, to this day, he's never spoken about it," she says. "That's his way of dealing with it - he's kept in whatever turmoil and trauma he went through in there."

Marten says she first crossed paths with Gordon in an incense shop in Tottenham, north London. Her family met him in the early days, they say, and were very apprehensive about the relationship. But by 2017 Marten and Gordon were backpacking around South America, and when they returned to the UK, Marten - now in her 30s - was pregnant with her first child.

There were concerns for the baby even before the birth.

Marten didn’t attend antenatal checks until six months pregnant and told midwives she lived in a camper van. When she stopped coming to appointments, worried medical staff issued a national alert - asking other hospitals to look out for her and Gordon. But they had already left London.

Marten later said they moved to Wales to get away from her family, who she said had hired private detectives to follow her as they disapproved of Gordon.

As Marten’s due date approached, she and Gordon were living in a tent near a supermarket car park in Carmarthen.

Arriving at hospital after going into labour, Marten showed signs of growing paranoia. She gave a false name and spoke with a fake Irish accent - telling staff she was from the travelling community.

But staff weren't convinced and, remembering the national alert issued in London, called the police.

There was a struggle and officers, assisted by other fathers on the maternity ward, had to use CS spray to restrain Gordon. He was arrested and later sentenced to 20 weeks in prison for assaulting two female officers, missing the first weeks of his new baby’s life.

With her partner behind bars, Marten went to stay in a placement for mothers and babies who need extra support. But there were soon questions about her ability to safely care for her child.

Social workers found bottles of wine in her room and warned Marten about the risks of falling asleep with the baby on her chest. Within six months a supervision order was made, allowing social services to monitor the child.

It was the start of a long journey through the family court system.

Judgments obtained by the BBC reveal the extent of the couple’s interactions with social services.

They also show Marten and Gordon often represented themselves instead of using lawyers, told lies, sometimes did not turn up for hearings, and appeared to deliberately avoid giving evidence.

By late 2018 the couple were back in London. They lived at various addresses, leaving without paying their rent more than once, according to landlords.

Former neighbours say Marten and Gordon did not appear to have jobs, rarely went out, and sometimes had blazing rows.

After the birth of their second child, social services were again involved.

But a family court judge became especially concerned after Marten fell from a first-floor window, while 14 weeks pregnant with her third child. When an ambulance crew arrived, Gordon initially refused to let them in, and police were called.

Marten spent eight days in hospital, but her unborn baby was not harmed.

When she got out of hospital, Marten fled to Ireland with her two children, but they were taken into care as soon as she returned. Marten and Gordon have never got them back.

Marten told police she had been trying to fix the TV aerial when she fell from the window, but a judge later decided, on the balance of probabilities, it was Gordon who "caused" her to fall.

The pair put their relationship ahead of "all other considerations", the family court judge wrote in February 2021, and viewed "all offers of support as hostile".

“The strong impression given by the parents is that of two people who are fiercely united in an unrelenting struggle against a non-existent opponent.”

Neighbours remember police officers calling round several times before the arrival of the couple’s third child and being asked to "let us know if you hear the sound of a baby".

Two weeks after the birth, this child was also removed.

Marten and Gordon were able to visit their children in care and would bring music to play or arrive with presents. They would comfort the children if they were upset, and sing and dance with them. Gordon planted apple seeds in the contact centre's garden - one for each member of the family.

But then he and Marten began missing the contact sessions.

They gave no explanation to the children for the gaps in their attendance and eventually stopped coming altogether.

By May 2021, Marten had given birth to a fourth child who was removed after only a week. Eight months later, in January 2022, a family court judge decided that although there were "vivid snapshots of what could, if this were the complete picture, be a loving and integrated family", all four of the children - all aged under 10 - should be permanently removed.

At the last minute, Marten offered to separate from Gordon in order to get custody of her children - but the judge simply did not believe she really would.

"When given the choice of considering what is right for the children and what is right for themselves, they picked themselves," Samantha Yelland, a senior crown prosecutor who worked on the case, says.

"They are besotted with each other - to the extent they prioritise each other over their children."

In September 2022, Marten was pregnant again. Fearing this baby would be taken away, she and Gordon left their home in south-east London - again without paying the rent - and made preparations to disappear.

Marten had been stockpiling money, and over the next four months she and Gordon lived in various AirBnBs, moving on frequently to avoid detection.

She concealed her pregnancy so carefully that, had their car not burst into flames on the motorway in January 2023, the existence of their new baby may have remained a secret.

Without Marten’s passport, which had been left in the car, they were unable to leave the country. Instead she and Gordon headed south, eventually reaching the coast near Brighton, where they lived rough in a small, flimsy tent in the depths of an English winter.

As the search for the missing family continued and media coverage intensified, there were sightings of Marten and Gordon with their baby, and they were captured on CCTV.

Victoria was seen inadequately dressed for cold weather - sometimes without socks, a hat and with no blanket. Her parents bought a buggy that was inappropriate for a newborn, then dumped it the same day and carried her around zipped inside Marten’s jacket.

Marten says she fell asleep in the tent while breastfeeding Victoria inside her jacket. She claims she woke up slumped over the baby with her forehead on the ground. Victoria was no longer moving. "She was completely limp" and her lips had turned blue, Marten told detectives.

She and Gordon tried to resuscitate their baby by breathing into her mouth and pumping her chest. But there was no response.

"It was one of the worst things I ever saw in my life," Gordon told police.

The couple carried her body around in a carrier bag - and even took her to the beach in Brighton. They said they had wanted to bury her but had eaten so little while on the run they didn’t have the strength to dig a hole deep enough. Marten considered cremating Victoria and had bought a bottle of petrol - but then had second thoughts.

"I do not think it is anything I will ever move on from," she later told a court.

After 54 days, police officers tracked down Marten and Gordon and they were arrested. Victoria’s body was found two days later.

A pathologist concluded it was not possible to determine the cause of her death, but said the baby could have died from the cold or co-sleeping.

Constance Marten, 38, and Mark Gordon, 51, denied harming Victoria and concealing her death, but have now been found guilty of manslaughter by gross negligence. At their first trial they were convicted of child cruelty, concealing baby Victoria’s birth and perverting the course of justice.

The couple’s behaviour throughout their Old Bailey trials showed their enduring paranoia and distrust of authority. They were disruptive and seemed to have little respect for the criminal court. At one point, the judge accused them of trying to "sabotage" the process.

Marten denied her baby had been exposed to dangerous conditions, saying she was kept warm inside her jacket. She branded social services an "abomination" and said her four surviving children had been "stolen" from her "by the state".

She told the court her family had been riven by arguments over her grandmother’s will. Giving evidence, she referred to a "traumatic" childhood event involving a family member. She said she had "spoken out about serious abuse", and told the court her family had tried to take her children away "as a way to get back at me".

"You are up against these people who will stop at nothing," she said.

The jury heard Marten’s parents had hired private investigators to try to track her down on three occasions.

Gordon’s barrister described Marten as a "lioness" who loved her "cubs". Her own barrister said Victoria’s death was "a terrible, tragic accident".

Gordon said it was the police’s fault their daughter had died. The manhunt had "forced" them to go camping on the South Downs in circumstances that were "not ideal".

But the prosecution barrister said lies had fallen from Marten’s mouth "like confetti in the wind". Marten and Gordon were "selfish and arrogant individuals", he said, and "caught in the middle of that toxic relationship was a baby that was manifestly not being cared for properly".

Victoria was the fifth child of two chaotic parents who had already had four children taken away. It is not known exactly when she was born - or when she died. She had never seen a midwife, or a doctor, or been given a safe, warm home to live in. Her parents made decisions that put her life in danger and ultimately led to her death.

As the prosecution said in court, Victoria "did not stand a chance".

The Child Safeguarding Practice Review Panel is carrying out a national review into Victoria's death, to examine how "agencies can better safeguard children in similar circumstances".

If you, or someone you know, have been affected by any of the issues raised, help and support is available.

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