"" January 21 episode called "Bloodlines" has been teased with a preview attached to the end of the show's December marathon. The CW is re-running the first half of season 1, two episodes at a time, beginning Monday, December 14 to Friday, December 18.
In "Bloodlines", Stefan and Damon's long lost sister, Maria comes for a visit and seeks revenge. It is up to the brothers to stop her before the truth is out. The mysterious man Elena meets on the road reveals that he is a vampire, and Elena is bitten by him, which Stefan learns later, forcing him into revenge against the unknown killer. Also, a new witch comes to town, Alyssa.