|aSummary: Twins Andrew and Evie have been chosen to perform an important and dangerous task. Everything they encounter is more complicated than it appears, and no one's identity can be relied on. They have only each other, and Spy X.
A year after their mother disappeared, twelve-year-old twins Andrew and Evie move to yet another town with their soldier father only to receive a mysterious package full of strange objects from 'Spy X' along with a warning to trust nobody.