: Transformed into a vampire by Katherine, Caroline evolves from a "shallow" high school girl into a confident, strong supernatural being.
: The season introduces Elijah and Klaus Mikaelson , the world's first vampires. Klaus , a vampire-werewolf hybrid, serves as the season’s primary antagonist. The Vampire Diaries - Season 2
: The Lockwood family curse is triggered when Tyler Lockwood accidentally kills a peer, leading to his first transformation and the introduction of his uncle, Mason Lockwood. Major Character Evolutions : Transformed into a vampire by Katherine, Caroline
The season consists of 22 episodes that aired on from September 2010 to May 2011. Saying Farewell to 'The Vampire Diaries' | The Nerd Daily : The Lockwood family curse is triggered when
: His character deepens as he struggles with his humanity and his unrequited love for Elena .
: Katherine returns to Mystic Falls with a plan to use Elena Gilbert to break a centuries-old curse involving a moonstone, vampires, and werewolves.
: Forced to face her heritage as a Petrova doppelgänger, Elena becomes more active in her own survival, eventually sacrificing herself (and being brought back) during Klaus's ritual. Episode Guide