Speaking to the Los Angeles Times, Dobrev explained that she "thinks" Elena will stick to her deal with Elijah (Daniel Gillies).
"Elena will do whatever it takes to keep everyone around her safe," she said. "So whether that ends up being keeping the promise, or in the spur of the moment something happens and she has to, in order to keep her friends safe, not keep her promise, then she will do whatever it takes."
Dobrev, who stars as Elena and Katherine, also revealed that it is possible that she could end up playing a third character on the show.
"Hypothetically," she said. "Because Katherine is the first doppelganger, that means there was one before her. So I guess we'll see what happens... I'm sure it would be interesting."
The Vampire Diaries returns for a new episode on January 27 at 8/7c on The CW.