We never learned exactly what the evil Mayor Lockwood (Robert Pralgo) was (vampire? werewolf? smoke monster?) before he lost his life in a burning basement in The Vampire Diaries season finale. But we may find out thanks to a mysterious new arrival headed to Mystic Falls.
“Our big new addition is Mason Lockwood, the mayor’s much younger and cooler brother, who has been estranged from the family,” says executive producer Julie Plec. “His return introduces a lot of questions about what is so special about that creepy Lockwood family.” My guess: they were unicorns with wooden vampire-killing horns.
Source: Vampire Diaries Online