Stefan was determined to get to know Elena Gilbert (Nina Dobrev, the upcoming film, "The Perks of Being a Wallflower"), who bears a striking resemblance to Katherine Pierce (also played by Dobrev), the beautiful but ruthless vampire the brothers knew and loved - in 1864. Damon, on the other hand, was intent on releasing Katherine from the tomb where he believed she was trapped by a witch's spell all those years ago. In the explosive finale of season one, Elena's uncle Johnathan (guest star David Anders) set a plan in motion that resulted in Katherine's return.

In season two, Katherine's manipulations threw a wrench into the love triangle between Stefan, Elena and Damon, and the other residents of Mystic Falls were forced to choose sides as they fell victim to a new breed of danger. Stefan and Damon were later met with their greatest challenge yet - the arrivals of Elijah (guest star Daniel Gillies, "Spiderman 2") and Klaus (Joseph Morgan, "Ben-Hur"), two of the "Original" vampires. As Klaus went head-to-head with Damon and took a special interest in Stefan, he was also seemingly focused on breaking the "Sun and Moon" curse by sacrificing Elena. No matter what action the brothers took to protect Elena, Klaus would not be swayed from his mission, proving himself to be the most powerful vampire in existence. Ultimately, Klaus' sacrifice ritual proved deadly not for Elena but for her Aunt Jenna (Sara Canning, "Smallville"), whose violent death devastated both her family and her boyfriend, Alaric Saltzman (Matt Davis, "Legally Blonde").

Season three opens the door to the history of Klaus and The Original Family, as Klaus' motives for wanting Stefan on his side are finally revealed. As Stefan sinks deeper into the dark side, Damon and Elena struggle with the guilt of their growing bond, even as they work together to bring Stefan back from the edge. The ghosts from Jeremy Gilbert's (Steven R. McQueen, "Everwood") past have a powerful message they're trying to deliver to him, not to mention the impact they're having on his relationship with Bonnie Bennett (Kat Graham, "Honey 2"). After the emotional end of her relationship with Matt Donovan (Zach Roerig, "Friday Night Lights"), Caroline Forbes (Candice Accola, "Juno") grows closer to Tyler Lockwood (Michael Trevino, "Cane"), and a war erupts between their families.

Based on the series of books by L. J. Smith, THE VAMPIRE DIARIES is from Bonanza Productions Inc., Outerbanks Entertainment and Alloy Entertainment in association with Warner Bros. Television and CBS Television Studios with executive producers Kevin Williamson ("Scream," "Dawson's Creek"), Julie Plec ("Kyle XY," "Wasteland"), Leslie Morgenstein ("Gossip Girl," "Private") and Bob Levy ("Gossip Girl," "Privileged").