In season one, surviving a car accident which killed her parents, Elena reluctantly returns to school for her junior year and begins dating a mysterious new student named Stefan Salvatore.
It is later revealed that he is a 162-year-old vampire.
Stefan's brother, Damon, also begins falling for Elena.
After Stefan and Elena sleep together, she finds a picture of a woman named Katherine Pierce who looks exactly like her.
Maxfield's enhanced ripper-werewolf virus into Elena's body, infecting her.
Elena's friends are eventually able to find an antidote.
She is the biological daughter of John Gilbert and Isobel Flemming, and adopted daughter of Grayson and Miranda Gilbert.