Loyalty. Family. Trust. Olivia Calabrese has valued nothing more strongly since her mob boss father was arrested and her mother was killed in the cross fire. Even though her family sells illegal magical charms that have the nasty side effect of turning some wearers into berserkers—rage-filled monsters—she sees betrayal as a far worse offense than harming people. To prove her loyalty, she dreams of succeeding her father as head of the mob family. When her uncle, the current boss, is shot by a rival gang, she just might get her chance. But her cousin, her only competition, whispers something to her that throws her off track. He says her mother ratted the family out to the police. He says that her mother's death wasn't an accident, but a hit ordered by her father. Her entire worldview called into question, Olivia sets about hunting down the truth about her parents. And to complicate matters, she seems to be falling for a boy who's turning into a berserker—from her own family's charms. As her set of values shatters around her, Olivia must choose between staying loyal to her family or fighting against them.

Olivia Calabrese struggles to deal with the fact that her boyfriend Brice turns into a berserker—rage-filled monster—every night at midnight, and that if she ever has sex with him, she'll turn into one too. When she's not busy looking for a cure (that everyone claims doesn't exist) for the berserker virus, she's trying to deal with the threats her mob boss father Lucio levels against her newly formed jettatori "family." If that weren't enough, it's becoming clear that Tommy, her mentor and friend, is a double-agent for Lucio, feeding information to Lucio so that he can try to kill her with armies of berserkers. And to make matters even worse, her right-hand man Josh seems to be developing a crush on her, something that Brice is not particularly happy about.