Isabella Swan''s mother gets married for the second time. Her husband is a football player and he travels a lot. Because of that Bella decides to move from sunny Phoenix on the seaside to rainy, sleepy Forks to live with her dad for some time. There seventeen-year-old''s life changes dramatically, she is in the centre of attention of her new schoolmates. Only Edward Cullen, next to whom she sits during Biology classes, doesn''t seem to be pleased to be close to her. After the first class together, he even tries to give up on Biology and choose some other subject, but it doesn''t work out. The situation changes when Edward a few days later saves Bella during a car accident at the school parking lot. He succeeds in doing that only because of his abnormal strength and quickness, which he later denies. Since this incident Edward hasn''t been hostile towards Bella anymore.
During an excursion to the beach Bella meets a friend from childhood, Jacob. He is Indian and lives in a reservation. Jacob tells Bella that according to old Indian tales, the Cullens (Edward, his parents and his four foster siblings) are vampires. They live in Forks because they manage only on animal blood and they don''t hunt people.
When Bella goes shopping to another town, she is attacked by a group of men. Edward saves her. They fell in love with each other. Edward explains his beloved what it is like to be a vampire. He can read people''s minds, but Bella is an exception - her mind is unreadable for him. Her blood tempts him greatly and he has to control himself better than when he is with other people.
Happiness of Edward and Bella is disturbed by the appearance of a few other vampires in Forks. One of them, James, decides to hunt Bella. The Cullens, who have already accepted Bella as a part of their family, want to save her. But Bella, to save her mother, surrenders to James. He bites Bella, but he hasn''t managed to kill her, because then the Cullens appeared and killed him. Edward, contorlling his thirst, sucked out James'' venom from Bella''s blood. Bella is taken to hospital, from which she comes back to Forks.
Bella goes with Edward to the school ball, awaited by all students. There Bella expresses her desire to become a vampire, but Edward refuses.
Summaries of the other parts of the cycle:
2) "New Moon": http://www.shvoong.com/books/horror/1870978-new-moon-second-twilight-series/
3) "Eclipse": http://www.shvoong.com/books/horror/1870987-eclipse/