When complications from her supernatural pregnancy leave Caroline's life hanging in the balance, Stefan and Valerie take extreme measures to try and save her and the babies. Meanwhile, after uncovering a dark secret about Damon, Enzo uses the information to force Damon into helping him track down Rayna Cruz, a ruthless vampire hunter who is on the loose. However, when Damon's actions inadvertently put everyone he loves in Rayna's path, he is forced to make things right before it's too late.