The first installment in the Night Huntress series introduces Catherine "Cat" Crawfield, a 22-year-old half-vampire, half-human living in the small town of Licking Falls, Ohio. Cat's mother, Justina, was raped by a vampire, and Cat was born five months later with supernatural abilities: enhanced strength, speed, night vision, and eyes that glow green when she is upset. Justina revealed the truth about Cat's father when Cat was 16, and since then, Cat has spent her weekends posing as vulnerable bait to lure vampires to secluded locations and kill them with a homemade weapon: a wooden-coated stake concealing silver inside. Cat has killed 16 vampires in six years, driven by a desire to avenge her mother and atone for what Justina has always told her is a monster inside her.
One night at a club, Cat senses a powerful vampire with pale blond hair and a clipped English accent. He dismisses her advances, so she kills a different, weaker vampire instead. The following evening, he reappears and agrees to leave with her but refuses to follow her usual routine. He knocks her unconscious, and she wakes chained in a cave. The vampire, who calls himself Bones, demands to know who sent her. Cat tells the truth: She is the child of a human and a vampire, and she hunts alone. Bones does not believe her until her eyes glow green, a trait only vampires possess. He proposes a partnership: Cat will serve as bait while he trains her and helps her find her biological father. Cat challenges Bones to a fight for her freedom but loses easily. He heals her injuries with drops of his blood, which has regenerative properties, and she agrees to his terms.
Over six weeks, Bones subjects Cat to brutal conditioning and educates her about vampire biology: Sunlight merely sunburns them, crosses and wood are useless, and only silver through the heart or decapitation can kill them. He gives Cat a makeover and coaches her in seductive conversation to prepare her for luring dangerous targets. Their dynamic shifts from hostility toward grudging camaraderie. Bones sends Cat to interrogate a ghost named Winston Gallagher in a local cemetery; Cat's half-vampire nature allows her to see and communicate with spirits. She bribes Winston with moonshine and obtains names of over a dozen recently murdered young women, suggesting a hidden pattern of killings.
Cat's first mission targets Sergio, a 300-year-old vampire worth $50,000, revealing that Bones is a professional bounty hunter. Bones interrogates Sergio and learns that a vampire named Hennessey is based in Chicago Heights. Afterward, Bones shares his history: Born Crispin Phillip Arthur Russell III in 18th-century England, the son of a teenage prostitute, he was shipped to the Australian penal colonies for thieving. In 1790, a friend who had been turned into a vampire changed Bones against his will. In return, Cat tells him about Danny Milton, a boy who pressured her into sex at 16 and abandoned her. Bones gives Cat 20% of Sergio's bounty, establishing the financial terms of their partnership.
Bones takes Cat to Bite, a vampire nightclub, for a rare evening off. Their attraction boils over into a passionate first kiss, but the night unravels when Hennessey himself enters the club. Cat improvises, approaching him as a woman on a bad date, while two young men slip a date-rape drug into her drink. The drug takes hold as Cat leaves with Hennessey, who drags her into the woods and begins feeding on her. She barely manages to press her panic button. Bones arrives and fights Hennessey, but a hidden bodyguard ambushes him, and Hennessey escapes. Bones later returns to Bite and finds the two men raping an already-dead girl in a van. He kills them both.
Cat begins college and is befriended by Stephanie, a classmate who, after days of cultivating Cat's trust, pulls a gun and tries to kidnap her. In the struggle, Stephanie is accidentally killed. Bones reveals Hennessey's full operation: For decades, Hennessey has been kidnapping vulnerable young women, forcing them into prostitution, and auctioning them to vampire clients. Cat and Bones travel to Charlotte, North Carolina, to pursue Charlie, one of Hennessey's recruiters. They kill Charlie and his partner and rescue Emily, a brutalized young woman left nearly catatonic. Charlie reveals the operation involves about 20 people and is expanding internationally.
Cat and Bones consummate their relationship, a transformative experience for Cat, who has carried shame from her encounter with Danny. Their bond deepens as they continue dismantling Hennessey's network, learning about his enforcer, Switch, and a mysterious new source of protection. Francesca, a vampire forcibly turned by Hennessey 93 years ago, offers to spy on him in exchange for Bones's protection. Before she can relay her discovery, Francesca is found dead, her body decomposed to its true age. Bones believes she killed herself rather than be captured.
The situation escalates when police detectives connect Cat to an old vampire killing through Danny Milton's testimony. Since Hennessey has connections in law enforcement, Cat's identity is exposed. She and Bones race to her grandparents' house and find both grandparents murdered. Justina has been taken alive.
Hennessey's men leave a coded note arranging a meeting. Cat drinks a large quantity of Bones's blood, which temporarily heightens her strength and speed to near-vampire levels. At the rendezvous, approximately 25 vampires hold Justina inside a house. Cat calls the police, then crashes the car through the front wall. She and Bones kill the majority of Hennessey's forces. Cat drives a silver knife through Hennessey's back as he bites into her collarbone. Switch escapes; Bones chases him, leaving Cat behind. She is shot by police and arrested.
A corrupt police lieutenant attempts to kill Cat during transport, but she overpowers him and extracts a confession: Governor Ethan Oliver of Ohio is Hennessey's secret human partner. Oliver used Hennessey to eliminate vulnerable populations, making crime rates drop to boost his political career while making police reports disappear. Oliver now plans to bomb the hospital where the rescued girls are being treated. Cat fights her way into the governor's mansion, kills Oliver, and surrenders.
In the hospital, Don Williams, head of the FBI's classified Paranormal Behavior Division, offers Cat a position commanding a government vampire-hunting unit. His associate, Special Forces Sergeant Tate Bradley, accompanies him. Cat initially refuses, but Justina delivers an ultimatum: She will disown Cat if Cat continues her relationship with Bones. Cat accepts Don's offer to protect both Bones and her mother, negotiating strict conditions including commanding her own team, ensuring Bones is never pursued, and serving a limited term.
Bones intercepts Cat's military transport, stopping the car by stepping in front of it at highway speed, a feat only a Master vampire, a powerful high-ranking vampire, can survive. He informs Cat that he tracked Switch to Indiana and killed him, leaving the body in the woods near Cedar Lake. He carries Cat and her unconscious mother to a safe house, planning to flee the country. That night, Cat writes farewell messages on a steamed bathroom mirror to coordinate with her mother without Bones hearing. After a final night together, she tells Bones she will love him every day until she dies.
The next morning, Cat takes her mother and contacts Don's agents. She presents the decomposed body of Switch, dressed in Bones's jacket, as evidence that the vampire is dead. Catherine Crawfield is officially declared deceased. Cat begins her new life at a military facility, healing the injured Tate with a transfusion of her own vampire-enhanced blood and declaring him the first member of her team. The novel closes with Cat recalling Bones's earlier promise that if she runs from him, he will chase her and find her.