Everything about Anna's life is a secret. Her father works for the Branch at the helm of its latest project: monitoring and administering treatments to the four genetically altered boys in the lab below their farmhouse. There's Nick, Cas, Trev--and Sam, who's stolen Anna's heart. When the Branch decides it's time to take the boys, Sam stages an escape, killing the agents sent to retrieve them. Anna's father pushes her to flee, making Sam promise to keep her away from the Branch, at all costs. Now on the run, Anna soon discovers that she and Sam are connected in more ways than either of them expected. And if they're both going to survive, they must piece together the clues of their past before the Branch catches up to them and steals it all away.