When residents of the affluent Southfields area of south-west London notice foul smelling smoke coming from a home on Wimbledon Park Drive in September 2017, firefighters arrive to make sure the house isn’t in danger. Nothing could prepare them for what they find instead – the burning human remains of French au pair, 21-year-old Sophie Lionnet. 

Suspicions are immediately cast on Sophie’s employers, socialite Sabrina Koudier and her long-term partner Ouissem Medouni. But why would the stylish couple want to harm their young nanny? And what does former boy band member Mark Walton have to do with it? What emerges is a tale of lies and blackmail so extreme that it beggars belief.