Caught up in her employers strange fantasy land, au pair Sophie suffered a horrific end.

I￼t was September 2017 and the smell of barbecue wafted through the air.

Far from the pleasant smell of food cooking though, neighbours reported a foul stench.

Eventually, firefighters were called to the home of glamorous couple Sabrina Kouider and Ouissem Medouni, where the smell was coming from. But they weren’t enjoying a family cook-up in the yard, they were trying to cover up a sinister and horrific crime.

The couple were calmly barbecuing a chicken and next to it, was the charred remains of a human body. Ouissem, 40, tried to pass off the burned body as the carcass of a sheep, but shocked firies noticed fingers and a human nose.

The chicken they cooked to try and disguise the crime Credit: That's Life!

It wasn’t long before the body was identified as the couple’s nanny, 21-year-old Sophie Lionnet.

That’s when a tangled and unbelievable motive for murder started to emerge...

A year before, Sophie had moved from France to live with the couple to look after their two children.

The girl, described as ‘kind’ and ‘gentle’ and as someone who ‘loved making people happy’, was unwittingly drawn into Sabrina’s obsessive fantasy world.

Sophie was described by friends as gentle and timid Credit: That's Life!

The 35-year-old suspected Sophie had been sent to spy on the family by her ex-boyfriend, Mark Walton. He later said he’d never even met Sophie, but paranoid Sabrina was convinced the two were having an affair.

Police found hours of video footage recorded by Sabrina and Ouissem, showing a terrified Sophie being accused of being a paedophile and a spy. They insisted Mark had sent Sophie to their home to drug and sexually abuse their kids and frame them. She was threatened with rape, prison and violence.

For 12 days, her employers refused to let her out of their two bedroom apartment and her passport and return ticket home were also never found, suggesting the couple had confiscated them. Frail and terrified, Sophie was unable to escape.

While being water-boarded in the bath, in a desperate bid to live, Sophie falsely confessed to being in a relationship with Mark.

Hours later, she was dead. How she was murdered was impossible to discover due to the state her body was found in.

Sabrina and Ouissem were jailed for life Credit: That's Life!

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Post-mortem tests did show the violence had ramped up and she’d suffered fractures to her sternum, four ribs and her jawbone in the days before her death.

After Sophie’s death, Sabrina and Ouissem both denied murder, each accusing the other of the vile act.

In court, Sabrina blamed her financial analyst partner for waterboarding Sophie in the bath.

She said Ouissem then wanted to have sex with her and, in shock, she allowed him to satisfy himself while Sophie’s body lay nearby. ‘I said “What are you doing?”. When he finished he said he was so stressed,’ Sabrina explained in court, adding that she was crying throughout the experience.

However, the judge saw a different side, describing the case as bearing the hallmarks of a psychosis known as folie a deux, or ‘madness of two’. This is defined as a delusion shared from one individual to another.

The remains of Sophie's charred glasses Credit: That's Life!

Sabrina, who had what’s called borderline personality disorder, was the driving force and Ouissem, the weak, willing party. The court heard how Sabrina had long been fixated with her ex, Mark.

After splitting up after a two-year relationship, Sabrina reported him to police more than 30 times and received a caution for falsely branding him a paedophile on Facebook. She also falsely accused him of sexually abusing a cat and hiring a helicopter to spy on her.

When naive Sophie came into their lives, Sabrina created a fantasy world, casting Mark as an evil villain who seduced Sophie with sex and promises of Hollywood stardom.

Ouissem then became an ardent believer of his girlfriend’s twisted reality, the jury heard.

Sophie's mother Catherine attend the funeral Credit: Getty

Prosecutor Richard Horwell, QC, told jurors that neither were prepared to admit the truth – that they killed Sophie out of ‘revenge and punishment’. He said their ‘unhealthy, myopic, all-consuming and groundless’ obsession with Mark had deprived them of reason and turned their nanny into ‘something less than human’.

In May, the pair were both found guilty of murder, with Sabrina collapsing in tears at the verdict, and Ouissem hanging his head. They were jailed for life, with a minimum of 30 years.

Sophie’s parents, who had little idea of what had been happening to their daughter, were often in tears during the trial. Sophie’s mother, Catherine, described her daughter’s killers as ‘monsters’.

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