It's 1927 and Elise Saint and the reaper she loves, Layla Quinn, are on the run, staying at the hideout of a gangster friend. New York isn't safe for either of them: Layla murdered a doctor with ties to the powerful Saint family, and Elise killed the matriarch of the Harlem reapers. Both of the dead were part of a dark conspiracy behind the so-called "cure" for reapers, but few in the city know the truth Layla and Elise discovered. Reapers are going missing, rumored to have been abducted for secret experiments. And Elise's beloved little sister Josi, a pawn in the conflict between Saints and reapers, has been poisoned with the reaper affliction--bitten, but not quite turned vampire--and is being kept hostage by their father. Meanwhile, the new leader of the Harlem reapers has joined forces with a female gangster who has a score to settle with Layla. With shifting alliances and power changes in the city's underworld, Elise and Layla can't trust anyone, not even one another. But once they learn about the new mayor's plans to assemble a reaper army to clear out the city's undesirables, Lalya takes charge of her reaper clan, bringing them together with rogue reapers and gangsters to fight back.

And when Josi Saint begins to show reaper-like abilities, Layla and Elise discover the power of shared blood between humans and reapers, making the two lovers stronger together. Yet ultimately one of them will have to choose between reaperhood and humanity--and sacrifice everything.