Adam is a charismatic tutor who charms his way into the life of the wealthy Tanner family while they vacation in Greece. When their nanny falls ill, Adam orchestrates his way into their London home, and his true vengeful nature begins to emerge.

Adam now starts to turn Jamie Tanner and Nat against each other while secretly plotting to bring down the entire family. When Adam's obsession with the family raises questions, those who dig deeper into his past find themselves playing a dangerous game. With his world collapsing around him, Jamie starts to realize that Adam may be responsible for all their recent disasters - but is it too late to save his family?