Lily Yu is a San Diego police detective investigating a series of grisly murders that appear to be the work of a werewolf. To hunt down the killer, she must infiltrate the clans. Only one man can help her - a were named Rule Turner, a prince of the lupi, whose charismatic presence disturbs Lily. Rule has his own reasons for helping the investigation - reasons he doesn't want to share with Lily. Logic and honor demand she keep her distance, but the attraction between them is immediate and devastating - and beyond human reason.

Touch-sensitive FBI Agent Lily Yu is recruited by the Secret Service to help identify elected officials who have accepted demonic pacts - bringing Lily and her werewolf bond-mate, Rule, to DC just before the holidays. But Lily must turn to fellow Agent Cynna Weaver for help when Cynna's former teacher, a demon master, emerges as the main suspect behind the pacts. After a demon commits a gruesome murder, sorcerer Cullen Seabourne joins the team racing the clock to find the apprentice of evil who uses demons to kill.

FBI Agent Lily Yu is in North Carolina with her lover and mate, Rule Turner, Lu Nuncio of the Nokolai werewolf clan. He is there to take custody of his son from the boy's grandmother. It's a purely personal trip until Rule, in wolf form, finds three bodies in a shallow grave. They carry the stench of death magic, which makes the murders a federal crime. Lily takes charge of the investigation and soon realizes that nothing adds up - not the motives or the main suspect, who is behind bars when death strikes again. 

Lily Yu and Rule Turner’s engagement announcement is stirring up ugly passions in the Humans First camp. There’s hate mail. Death threats. Lily’s car is vandalized. But professionally, things are going smoothly...until a lupus in Tennessee goes on a killing spree. Then Rule's brother, Benedict, catches a lovely intruder - twice. The first time she's sneaking around the home of the leader of Humans First. The second time, she sneaks into Nokolai Clanhome with a mysterious potion.

Lily Yu and Lupi Prince Rule Turner have a bigger problem than their families not accepting their impending human/werewolf mixed marriage. A powerful ancient nemesis of Lily's grandmother has come to San Diego to turn the city into a feeding ground.