One Missing Girl. Two Million Suspects. Ruby is a vlogger, a rising star of YouTube and a heroine to millions of teenage girls. And she's missing ... But she's an adult – nothing to worry about, surely? Until the video's uploaded ... Ruby, in the dirt, pleading for her life. Enter Detective Inspector Kate Riley: the Met's rising star and the head of a new team of investigators with the best resources money can buy. Among them, Detective Sergeant Zain Harris, the poster boy for multiracial policing. But can Kate wholly trust him – and more importantly, can she trust herself around him? As hysteria builds amongst the press and Ruby's millions of fans, Kate and her team are under pressure to get results, and fast, but as they soon discover, the world of YouTube vloggers and social media is much darker than anyone could have imagined.