Tessa tells Damon she's seen the former lives of Elena and Stefan fall in love over and over again, but what if one of their ancestors didn't. What if there's another Doppelganger running around and instead of falling for Silas' doppelganger, she had killed him instead? See what happens when the Doppelganger comes into the lives of our favorite residents of Mystic Falls. Damon/OC