There's no other show on TV right now that delivers twists and surprises with quite the same emotional impact as "The Vampire Diaries," and the third season finale was no exception. Perhaps not since "Lost" has a TV show so consistently delivered those shocking moments in every episode that make fans outwardly gasp or yell out "OMG!"
For a season filled with major plot developments (Jeremy being able to see ghosts, Stefan's journey to the dark side, the death of Mikael, Esther's plot to kill her children, and Alaric's transformation into a vampire), the Season 3 finale managed to up the ante and deliver more gasps per minute than any other episode all season.
The events of the penultimate show set up the following conflicts in the finale: If Elena dies, newly minted vampire/vampire hunter Alaric also dies. And if Klaus dies, then (he says) the Salvatore brothers will also die.
The death of Klaus is truly one of the most shocking moments in the episode. But not as shocking as the realization that Klaus isn't dead: Bonnie's helped him to jump into Tyler's body. And if he stays there, that could make Caroline's love life extremely complicated next season.
Also dead by the end of the episode is Alaric, thanks to Elena's death at Wickery Bridge (more on that later). With vampire Alaric dead, the ghost of the good Alaric has decided to haunt Jeremy, which is great news for fans who weren't ready to say goodbye to the character.
Now for the biggest shocker of the night. Through a series of dreams and flashbacks, we see Elena on the day her mom and dad died. Strangely, her mom gives her information in dealing with Matt that relates to dealing with her feelings for Damon and Stefan.
"You're setting him free. You're not gonna lose him," her mom says. That leads Elena to tell Damon that she might have loved him more had she met him first. Which of course, she did. Damon made her forget meeting him, because he wanted to keep a low profile.
Alaric has arranged for Dr. Fell's medical license to be revoked for using vampire blood. But it's that use of vampire blood on her patients that sets up the most dramatic cliffhanger in the show's history. Elena died with vampire blood in her system.
We can assume Season 4 will open with Elena in transition. Granted, it probably won't stick. As the center of the show, she needs to stay human, a desire she expressed very strongly at the end of Season 2. Bonnie will probably find some magical way to restore her humanity and prevent Elena from turning.
But with Elena in transition, then she will likely forget all former compulsions, and she'll remember meeting Damon for the first time, without him having to tell her. That will set up a very interesting dynamic between Elena and the Salvatore brothers next season. And should Elena become a vampire, then she'll have an eternity to decide which Salvatore brother she loves the most.