Nyx Slaughter is an assassin, a killer for hire. Her targets - rogue vampires, werewolves, and other supernatural beings who break the code. Nyx is under the care and tutelage of the Collective, on whose doorstep she was left as a newborn. She is torn between her friendship with Ryan (a werewolf), Sebastian (head vampire), and later Alex (head werewolf). Nyx also has to contend with the unwanted attentions of Tommy, an old enemy who is obsessed with her.Nyx always thought she was human, but she discovers her secret heritage, along with some amazing new powers she never knew she possessed. She learns to control them under the guidance of Sebastian and Alex, who also convince her to leave the Collective and join their Resistance movement. With Sebastian's help, Nyx sets up her own business as a private investigator, a plot device that should lead to some interesting storylines.This book contains some fascinating twists on the traditional vampire and werewolf myths. It is humorous and sexy, but some of the dialogue is a bit stilted. The author does a great job of weaving the back-story into the elements of the story itself. This book ends on a cliff-hanger, leaving it open to the sequel, "Night Marks", which I can't wait to read.