As Damon's behavior escalates from destructive to deadly, Stefan begins to regret their last conversation and decides to track Damon down and intervene. For reasons of her own, Elena volunteers to come along. Dr. Wes enlists the Travelers to set a trap that will once again test Damon's friendship with Enzo. After a heart-to-heart talk with Nadia, Matt enlists Caroline and Tyler's help to protect Elena, leading to a violent confrontation. Later, when Stefan tries to comfort a dejected Caroline, their conversation leads to a horrifying realization.