Months after Damon and Enzo mysteriously vanished from the Armory vault, Stefan tirelessly pushes forward with their search, while Bonnie struggles holding onto hope that they will be found. Meanwhile, a dangerous encounter with an unexpected visitor leaves Caroline and Alaric fearing that someone - or something - may be targeting their family. Finally, after following some mysterious clues, Stefan realizes that whatever has a hold of his brother may have a more damaging grip over him than he could have ever imagined.

As Enzo continues to fight the control over him, Bonnie finds herself at the center of a deadly game and forced to make a heart wrenching decision involving two of the most important people in her life. At the Armory, Alaric researches a mysterious artifact that he hopes will help in their fight to get Damon and Enzo back. Finally, Damon's downward spiral leads him to Tyler Lockwood who attempts to talk some sense into him before it's too late.