In an alternate version of our world, vampyres develop from human beings in a process known as “the Change.” One day, a Tracker puts the Mark of a crescent moon on 16-year-old Zoey Montgomery’s forehead, symbolizing she has been chosen by the goddess of night to become a vampyre. Zoey is concerned because many kids don’t survive the transition. She also knows her conservative religious mother and stepfather won’t be happy.
Zoey sees Heath, the boy she’s been dating, and he notices her Mark immediately. He and his friends take off in a hurry, and he scrapes his hand against the pavement. Zoey is horrified by her attraction to his blood. At home, Zoey’s mother and stepfather are horrified by the news of her selection. Zoey realizes she will die soon if she doesn’t get to the House of Night, a special school for vampyres. Her stepfather refuses to drive her to the school, instead calling people to come and pray over her for healing.
Zoey escapes out her window and heads for her grandmother’s house. She falls and has an out-of-body experience, in which she meets a beautiful woman. The woman is Nyx, the vampyre goddess of night. Nyx says Zoey has been chosen to be the first true Daughter of Night in this world. She has the wisdom of her ancestors as well as knowledge of the modern world. It is Zoey’s destiny to be a powerful leader and restore balance between good and evil.
Zoey’s grandmother takes her to the House of Night. The High Priestess Neferet wonders why the girl’s Fledgling Mark has been colored in, symbolizing she is already a vampyre. They begin to tour the school, but Neferet gets called to the infirmary. She instructs Zoey to wait for her at a nearby bench. Zoey tries to follow Neferet’s instructions, but takes a wrong turn. She sees a teenage girl on her knees in front of a boy, ready to give him oral sex. The boy’s eyes lock on Zoey’s and the two share a connection. He pushes the other girl away as Zoey flees the hallway. Neferet returns to lead Zoey to her dormitory. There, the same girl Zoey saw in the hallway shows her to her room. Her name is Aphrodite, and she warns Zoey not to mess with her.
Zoey immediately warms up to her new roommate, Stevie Rae. In the dining hall, Zoey meets Stevie Rae’s other friends — Damien, Erin and Shaunee. Damien is one of the few gay vampyres. Erin and Shaunee call each other “twin,” although Shaunee is a black Northern girl and Erin is a white Southerner. Zoey learns Aphrodite is the leader of the Dark Daughters, a group of upperclassman in charge of school spirit. Before Zoey finishes dinner, Aphrodite approaches her table and invites her to take part in a Full Moon Ritual the following night.
While walking to the Full Moon Ritual, Zoey comments on Stevie Rae’s dark mood. Stevie Rae explains that a Fledgling in one of her classes died from the Change. She says it is common for Fledglings to become sick and die suddenly. A female vampyre greets the girls at the Ritual, placing the mark of a pentagram on their foreheads. The students and teachers take their places in a circle in a room that used to be a church. They call on spirits and elements and magic, and Zoey is electrified.
After the ritual, Zoey attends the meeting of the Dark Daughters. Erik greets her at the door and places another pentagram mark on her forehead. He is one of the Dark Sons, the male auxiliary to the Dark Daughters. As the ritual begins, Zoey sees that it is much like the one she just attended, but the Dark Daughters are using incense laced with marijuana. Aphrodite performs a sexual dance and gives Zoey wine to drink. After the ceremony, Zoey sees Elliot, an annoying kid from her classes, slumped in a chair. She questions others and they call him their “refrigerator” for the evening. They have mixed his blood with the wine used in the ceremony. Zoey is appalled to learn that she not only drank his blood, but that she loved the taste.
Zoey escapes outside and vomits. She then hears a cat meowing in a tree above her. In an effort to calm herself, she coaxes the cat down and names it Nala. Heath and Zoey’s former best friend, Kayla, then arrive. They are drunk and prepared to take her home. Zoey asks Kayla and Heath to leave. Heath is reluctant, telling Zoey that she is more attractive than ever. They begin to kiss, and she accidentally scratches his wrist. When he pulls away to suck the blood off, Zoey can barely control herself. Heath seems to be mesmerized by her. The two kiss again, and Zoey is energized when she tastes the blood on his lips. Kayla’s screams bring Zoey back to reality. She forces Heath to leave.
Zoey breaks down in tears, confused by all that’s happening to her. Erik Night finds her and offers her a tissue. When Zoey admits she saw him and Aphrodite in the hallway, he says he and Aphrodite are no longer together. He admits he followed Zoey out of the ritual because he figured Aphrodite hadn’t told her about the blood mixed with wine. He tells her she should mention to Neferet that Heath seemed to be entranced by her. Erik walks Zoey back to her dorm and tells her if she ever wants another sip of blood, he’s the man for her. He takes her hand and softly bites her wrist. Zoey’s body immediately responds to the gesture in a sexual way.
Zoey tells Stevie Rae about some of the night’s events. Stevie Rae tells her that Nyx’s gift to Aphrodite is prophecy, and the girl has detailed visions of the future. The previous week, Aphrodite saw a plane crash and could tell Neferet the airport and plane number so the accident could be prevented. Zoey realizes that Aphrodite invited her to the ritual hoping Zoey would get freaked out by drinking blood and refuse to join the Dark Daughters. Zoey knows she’ll have to join the group or Aphrodite’s plan will have worked.
The following morning Zoey talks to Neferet about Heath and her unnerving lust for blood. Neferet urges Zoey to call her Grandmother Redbird for comfort. Her grandmother reminds Zoey about their ancestors’ Cherokee purification ritual and recommends she perform it right away. Zoey tells her friends, and they offer to help her.
That night, Zoey and her friends purify themselves in the Cherokee tradition and form a ritual circle. The others are amazed and excited when, as Zoey calls each element, they sense her affinity for it. Once all the spirits are called, Zoey says a prayer, hoping that the spirits will carry it to Nyx. She asks the spirits and the elements to help her be strong and become the person she is supposed to be. Later, Erik finds her and walks her home. She agrees to watch movies with him that weekend, and the two kiss passionately.
The following day, Zoey is shocked when Elliot begins spewing blood in their English class. Zoey is upset further when her cell mailbox is filled with messages from Heath expressing his need to see her. On her way to Neferet’s office, she stumbles upon Aphrodite, who’s in a trance. She drags Aphrodite into Neferet’s office. Aphrodite is clearly horrified at what she’s seeing. She keeps muttering about blood and things that are dead, but not dead. Neferet wakens the girl out of her vision and sends Zoey away.
On the way to the Dark Daughter Samhain ritual, Zoey sees Elliot and knows he’s some kind of undead being. He threatens her, but Nala attacks him, and he escapes. Aphrodite leads the group out into the town to a special meeting place in a gazebo. Aphrodite chants a prayer calling for undead spirits to cross into the land of the living. As ghostly figures emerge from the fog, Aphrodite offers them a goblet of the wine/blood mixture. As the spirits start toward the drink, Heath arrives. The spirits leave Aphrodite’s body and attack him. Other members of the Dark Daughters and Sons flee.
Stevie Rae has dropped the cloak disguising her as the “refrigerator.” Damien, Shaunee and Erin also come out of hiding. The four friends use Aphrodite’s candles and form another ritualistic circle. Zoey calls upon the elements and asks the ghosts to accept the offering of blood and wine she pours out at her feet. At first the spirits refuse, continuing to slash at Heath and Erik. Zoey then commands them, in Nyx’s name, to return to the circle for their sacrifice.
Neferet arrives and commends Erik and Zoey for their bravery. She removes Aphrodite from her positions of High Priestess in training and leader of the Dark Daughters and gives the titles to Zoey. On the way back to the school, Zoey separates from her friends to find Nala. Aphrodite approaches her with a warning that they are both being used. When Zoey questions her about her earlier vision, Aphrodite cryptically replies that it’s only the beginning.