One week after Elena Gilbert has come back from the dead, she is in a childlike state, unable to read and almost completely unable to speak. Her understanding is impaired but not completely absent. Because of Elena's seeming impairments, Stefan Salvatore is protecting her from her best friends: Meredith Sulez, Bonnie McCullough, Matt Honeycutt and Caroline Forbes. Although he feels that it is wrong to drink Elena’s blood when she is unable to give reasoned consent, Elena makes gestures to insist that he drink, and Stefan does. Damon Salvatore watches outside Caroline’s window as Caroline talks to an independent image of herself. Damon believes the mirror-Caroline to be a supernatural evil force that is playing some sort of trick on Caroline. He feels a sharp puncture on his neck while he watches, which surprises him because mosquitoes do not bite vampires. After the mirror-Caroline goes away, Damon persuades Caroline to let him into her bedroom. He is about to bite her when he realizes that he is being influenced to do so by something, probably the supernatural evil force creating the mirror-Caroline. He rejects it and leaves. Afterwards, he goes around the town of Fell’s Church seducing and biting young women and shoplifting. He does not have sex with them because, as a vampire, he is impotent. Vampires only enjoy bloodlust and its satisfaction. Damon visits Stefan and Elena, beats up Stefan and drinks his blood, and demands the return of the leather jacket he gave Elena.
Stefan allows Elena’s friends to visit her. Suspicious of Caroline, who claims to have been raped by Klaus, Meredith and Bonnie require her to sign a blood oath that she will not hurt Elena, and they threaten to tell her future sorority sisters if she betrays Elena or Stefan. A crow appears and vomits blood on the paper they all sign. The blood-vomit is in gothic script and reads: “D. Elena is mine.”When the four humans show up at Stefan’s room in the boarding house owned by Mrs. Flowers, Elena is floating in a lotus position and exuding sheer goodness. Elena does not recognize any of them. She kisses Caroline, who is upset by Elena’s apparent lesbianism. Meredith explains that Elena is behaving like a prairie dog, as prairie dogs kiss one another when they meet to recognize one another. Caroline rejects this explanation. Bonnie thinks Elena is pure and therefore cannot be a pervert the way Caroline thinks. Elena kisses Meredith and Bonnie. Caroline, who is increasingly upset, says Stefan likes to watch girls kissing. Stefan uses his Powers to eject Caroline from the room. The others say negative things about Caroline, who overhears and reenters. Caroline starts to use Black Magic to attack the others, but Elena drives back the darkness with her White Power. She develops wings that glow, but then they disappear. Caroline leaves, and Elena kisses Matt while Bonnie and Meredith distract Stefan so that he will not have to watch his fiancé kiss another man. Meanwhile, Damon seduces a woman named Damaris, who he does not like, and drinks her blood. When he leaves her, he may have turned her into a vampire. He doesn’t know or care, but thinks her vampirism may be amusing when her husband finds her. Bonnie and Meredith have a sleepover together. In the middle of the night, Bonnie gets up and, in trance, starts to channel an entity speaking backward English. She records it on Meredith’s cell phone. Meredith transcribes the recording. It warns that Elena will have an Awakening that they should be prepared for. The next day, Stefan says that he is going to leave Fell’s Church with Elena because her reanimation has made her blood too attractive to vampires, who are attracted to Fell’s Church anyway because ley lines cross there. Bonnie is upset by the proposed departure.
As Bonnie, Meredith, and Matt drive home from the boarding house, they are surrounded and attacked by ambulatory trees, which poison the three humans with their sap. Bonnie uses her psychic powers to call to Damon for help, but even though he is nearby, he does not respond at first. When he does respond, he decides to save the nearly-dead Bonnie. Returning to the boarding house with her, he nearly runs into Stefan, who is driving with the floating Elena tethered to his car like a balloon. Damon realizes that Stefan is actually super-powered because he has been drinking Elena’s spiritually super-charged blood, and he was letting Damon beat him up before in order to conceal the power of Elena’s blood. Stefan volunteers to save Meredith and Matt while Damon cares for Bonnie. Damon rescues Bonnie by partially undressing her, floating her in a bath of warm water, and then feeding her his blood. Meredith, now fully recovered, threatens him if she finds he has removed Bonnie’s panties. Finding that he did not do so, she and the others relent. Bonnie, however, wakes up and accuses Damon of watching while the trees attempted to kill them all. The others reject Damon, who leaves in spite of Elena’s incoherent request that he stay. Stefan and Elena float in the forest together, kissing and drinking one another’s blood, while unbeknownst to them Damon watches jealously from a tree. Damon then discovers the presence of another person, Shinichi, who seems to have supernatural powers. The next morning, Elena wakes up able to speak. She and Stefan engage in kissing and possibly sexual intercourse. Then Stefan buys her a Jaguar. She and Stefan then go for a celebration picnic with Bonnie, Meredith, and Matt. During the picnic, Matt tells them that the fifteen-year-old Tami Bryce kissed him and rubbed up against him, and that he cannot understand why. Elena tells the others that she saw a tentacled monster inside Damon the day before. She says that when Damon ignored Bonnie, he was being influenced by a supernatural evil termed a malach. The others agree that a malach may have been affecting Tami and that they will mount a campaign to save the girls of Fell’s Church from the new evil. Meanwhile, Shinichi, now identified as a kitsune, and Damon are watching unseen. Damon says that he doesn’t want “his” girls—Bonnie and Elena--hurt. Shinichi puts Damon in a trance and encourages the malach inside Damon to grow larger and stronger.
Damon tells Stefan that there is a website referring to an organization, the Shi no Shi, that can turn vampires to humans. Stefan is suspicious but agrees to visit Damon in the woods at a particular time to learn more about it. He leaves a note on the computer for Elena and sneaks off while she sleeps. Damon changes the note to read that Stefan has decided to leave Elena for her own good. Elena wakes and believes that she has been abandoned by Stefan. She decides to find Stefan with the help of her friends. During a sleepover with Bonnie and Meredith, Elena decides that this is the Awakening referred to in Bonnie’s channeled message. Meanwhile, Matt is attacked by malachs on the way back from the boarding house. The next day, Matt returns to the boarding house, where Mrs. Flowers reveals herself to be a witch and binds Matt’s wounds. Matt has two unexplained punctures on his neck, which everyone dismisses. The sheriff calls the boarding house to warn Matt that he is a suspect for the removal of stop signs from intersections. Matt denies the charge. Meredith and Bonnie set out to visit Caroline to see if she is malach-infested. Caroline is scuttling on the ceiling of her living room like a lizard, and she runs under the bed in her mother’s room. When Caroline’s mother faints, Meredith and Bonnie carry her to her bedroom and deposit her on the bed. The possessed Caroline, or some other force, grabs their ankles. Bonnie calls Damon to help. Damon arrives, frees Bonnie and Meredith, kisses Bonnie, and leaves.
Matt and Elena visit Tami, who has super-glued a homemade stripper outfit onto herself. She makes sexual overtures to Matt, who is horrified. Matt and Elena then head toward the Old Wood for further investigations, while Bonnie and Meredith head to the house of a friend Isobel Saitou. Isobel has mutilated herself, and Dr. Alpert thinks she should go to the hospital. All set out, but Meredith and Bonnie leave to find Mrs. Flowers. In the Old Wood, Matt and Elena encounter Damon, who orders them to kiss and then have sex while he films them with a video camera. Elena at first tries to cooperate, but Matt objects and is tortured by Damon. Elena decides that Damon is not acting like himself. She attempts to rescue Matt by persuading Damon to drive away. However, she leaps out of the speeding car, hoping to make her way on foot to a nearby house. She is badly injured by her jump, however, and she cannot find the house because she is caught in a snowglobe trap designed by Shinichi. Damon suddenly comes to himself with vague memories of hurting Elena. He finds Shinichi and threatens to torture him. Shinichi reveals Elena’s location and how to cure her injuries, and he leaves Damon with a kitsune key that will magically open any door. Damon creates a door to whatever room he finds necessary to heal Elena. Being in a spot not covered by the fairytale rules governing his ability to tell her the truth, Damon confesses to her that he and Shinichi kidnapped Stefan and that Shinichi and his twin sister, Misao, are evil kitsunes who plan to destroy Fell’s Church. The kitsunes are the ones behind the malach, the ambulatory trees, and the sexually precocious and self-mutilating girls. Damon also drinks Elena's blood and realizes that it has amazing powers, including the power to restore a vampire's sexual potency. Damon’s possession returns, however, and he attacks Elena, who flees with the key through a series of doors. At last, she directs the key to open a door taking her to someplace the kitsune can’t see.
When Damon chases her to this place, Elena finds within herself a power she identifies as Wings of Redemption. Rainbow-colored wings open on her back and enfold her and Damon, who screams as he is redeemed from all his sins. He also forgets everything, so Elena opens up her violet-blue Wings of Remembrance, which allow him to remember. Damon realizes that he has been possessed by Shinichi and that he’d been playing the villain, and he calls himself an abomination, kisses Elena’s foot, and vows to be her slave. Elena then opens up her white Wings of Purification. Still with the wings open, she causes Damon to lie face-down on her lap and uses her fingernails to pull the malach out of his spine. The malach had originally entered via the puncture in Damon’s neck at that Damon mistook for a mosquito at the beginning of the book. Damon stands up and stomps on the malach to kill it. Damon and Elena then concoct a plan to defeat Shinichi and Misao. First, however, Elena makes a side trip to visit Stefan, who is imprisoned in a dungeon in a hell dimension. She makes him drink her blood to regain some of her strength. Meanwhile, Matt has regained consciousness. Tracking Elena, he ends up at the house she was trying to reach. There another girl, Kristen Dunstan, makes sexual overtures to him. He continues into the woods and finally runs across Meredith, Bonnie, and Mrs. Flowers. The four then encounter Isobel and Dr. Alpert. They reach the boarding house, but other possessed girls attack. Damon appears, and then two of the group are revealed to be Shinichi and Misao, who have been playing with them all along. Damon, Shinichi, and Misao take Dr. Alpert, Mrs. Flowers, Matt, Meredith, and Bonnie prisoner. Caroline is also present as one of the helpers of Shinichi and Misao.
Elena watches hidden from the trees and wonders if Damon has betrayed her while the others are herded into a clearing. Bonnie is tied spread-eagled to a makeshift altar by the ambulatory trees, and another walking tree with a penis approaches her. Damon magically summons a pair of scissors to cut out Meredith’s tongue. Elena hesitates, filled with doubt, but then she realizes that the solution to the situation is belief. She jumps off the tree where she has been hiding and, because she has belief, she develops a pair of golden wings, called Wings of the Wind, that enable her to fly. She seizes Misao and the scissors, and flies upward. Misao is heavy and Elena falters, but everyone calls out that they believe in her, and she flies higher. She starts to cut Misao’s tails off to diminish Misao’s power. Damon summons a magic sword and cuts Bonnie free. Misao begs for mercy and finally gives Elena clues where to find the magic key that will release Stefan. Shinichi agrees to give Damon a psychic map if Damon surrenders his memories of the last few days to him. Damon agrees even though losing his memories involves losing his redemption. Elena opens the Wings of Purification again and purifies the Old Woods, turning it into a place where flowers grow and removing the ambulatory trees. The good guys then let Shinichi and Misao go, but not before Misao admits to pretending to be Shinichi pretending to be the mirror-Caroline. Caroline says she is pregnant and needs a husband. The next day, Caroline informs her family and the sheriff that she is pregnant and Matt is responsible. A judge related to Caroline’s family signs an order for Matt’s arrest. Matt thus joins Elena and Damon in their quest to find and rescue Stefan. Damon refers to Elena as his princess of darkness, as he intends to win her away from Stefan. Here the first book of the Return trilogy ends.