Ava Delaney calls herself a hybrid - a living, breathing human who happens to have vampire poison running through her veins. The only thing greater than her thirst for human blood is her capacity for guilt. She does her best to avoid the human world, for everyone's sake.

When Ava accidentally enslaves a human while saving him from a vampire, she realises she has to look for help setting him free. Despite her misgivings, she expands her world but finds herself dragged into a possible vampire civil war. With the help of some new friends with ambiguous loyalties, she tries to find a way to keep her human, and herself, alive.