In February of 2023, a 37-year-old pediatric nurse was stabbed to death inside her suburban Virginia home, alongside a stranger from a dating app. But what appeared to be the scene of a sexual tryst gone terribly wrong quickly changed in the eyes of investigators the more they questioned the family’s live-in au pair. And when they did, a sinister plot revealed itself. This is the story of Christine Banfield. It’s also the story of Joseph Ryan, known as the Au Pair Murders.