On her 18th birthday, Bella Swan wakes up from a dream in which she sees herself as an old woman. She expresses her distaste with growing older than her boyfriend Edward Cullen, a vampire who physically stopped aging at 17. Despite her lack of enthusiasm, Edward's adoptive family throws Bella a birthday party. While unwrapping a gift, Bella gets a paper cut, causing Edward's brother, Jasper, to become overwhelmed by her blood's scent and attempt to kill her. Realizing that he and his family pose a danger to Bella, Edward ends their relationship, and the Cullens leave Forks, Washington permanently.

Edward's departure leaves Bella heartbroken and depressed for months. However, when her father, Charlie, wants her to live with her mother in Florida, Bella agrees to spend time with her friends. After a movie with Jessica, Bella sees a group of men on motorcycles. This reminds her of when Edward previously rescued her from an assault, and she sees his image warning her to stay away. Bella discovers that thrill-seeking activities evoke Edward's preserved image. She is also comforted by her deepening friendship with Jacob Black, a cheerful companion who eases her pain over losing Edward. When Jacob is unable to see Bella for weeks, she discovers that he is a werewolf, an age-old enemy of vampires. Jacob's pack members are on constant patrol for Victoria, a vampire searching to kill Bella due to the death of her mate, leaving Jacob little time to spend with her. Alone again, Bella returns to seeking thrill-inducing activities.