At the end of a repeat of episode "The House Guest", "The Vampire Diaries" released a promo for the next six episodes that will lead to the second season finale. Kicked off with the footage of Isobel's return in April 7 episode, the promo went on with Bonnie questioning her fate and Damon preparing to tell a hard cold truth.
"Vampire Diaries" went on a hiatus after February 24. When it comes back, Isobel arrives unexpectedly and her visit upsets Jenna. Meanwhile, Bonnie tries to harness her ancestors' power through a spell, and Matt informs the sheriff that his sister was killed by a vampire.
Speaking of Isobel, showrunner Julie Plec told Showtracker, "Isobel and John are going to have a parental sit-down with Elena expressing that they have an agenda that they believe will keep her protected." And when they do, Elena has "to decide whether or not either of them can be trusted."
In addition, Plec said, Stefan and Damon "will find themselves going up against each other and becoming increasingly more at odds about method."