The victim is apparently Sophie Lionnet, 21, who was caring for her alleged killer's children. Sophie has not been seen for a couple of weeks.
A mother-of-two accused of murdering her nanny with her fiance sobbed and yelled in French: "Tell them I didn't do it" as she appeared at the Old Bailey today.
Sabrina Kouider, 34, and Ouissem Medouin, 40, allegedly killed Sophie Lionnet and burned her body in the back garden of their £900,000 home in Southfields, south-west London.
Police discovered Ms Lionnet's charred body last Wednesday after neighbours noticed plumes of smoke and a rancid smell coming from the garden.
Today the pair appeared via video link from prison at the Old Bailey and Kouider began weeping and said in French: "Tell them I have killed nobody, please tell them, I beg you, please tell them I didn't do anything."
21-year-old Sophie, from Troyes, northeast France, had moved to the UK last year to improve her English and was reportedly paid £50 a month by Kouider, who had a son with Boyzone founder and Pop Idol judge Mark Walton.
A visibly distressed Kouider, dressed in a black top and with her dark hair in a bun, broke down in tears and said "I can't hear" as a French interpreter was sworn to help Medouin follow proceedings.
Prosecutor Bill Emlyn Jones said: "These two defendants appear before the court for the first time in connection with a charge of murder.
"There will be a hearing known as a PTPH on the December 12 2017. The trial date may well be the March 19 2018."
Prosecutors believe Medouni and Kouider are a couple, but say the precise nature of their relationship is not clear.
Judge Nicholas Hilliard, QC, remanded the pair in custody until a plea hearing on 12 December at the Old Bailey.
Medouni and Kouider, of Wimbledon Park Road, Southfields, southwest London, are charged with the murder but did not indicate pleas at the hearing.
Neighbours said they had noticed smoke coming from the garden on Wednesday, and an unpleasant smell in the days before.
One told the Evening Standard: "We complained to our landlord the day before about a bad smell. It was like a gas leak. He came in and had a look around but didn't see anything.
"They seemed quite normal but they always do. We would hear them having really loud arguments below there would be a woman's screams."
Another resident said: "We saw smoke and there was a foul smell. My son was being a bit cheeky and he climbed up the fence to look over and he saw a man sweeping up what we thought were sticks and putting them on the bonfire."
A woman living opposite said: "It definitely did not smell like a barbecue so I could not think what they were burning."
Kouider was arrested at the scene along with Medouni, 40, and later charged with the murder of the French au pair up to two weeks' ago, who was allegedly earning around £50 per month caring for her children.
Friends said she was unhappy and returning home to her parents in Troyes on Monday, which is 110 miles south-west of Paris.