In an interview with French publication Séries Mag, Ian Somerhalder provides a great deal of background on his character on The Vampire Diaries, along with the basis for his feud with brother Stefan.
Asked about Damon Salvatore, the former Lost star explains the blood sucker's origins and the way he's portrayed on the new CW series:
"He's a demonic being who attempts to corrupt his brother and push him into feeding on humans once again. Damon and Stefan are more enemies than brothers since the death of their respective loved ones, who transformed them both into vampires over 140 years ago. And when these two again fall in love, this time around with the same young woman, things will really turn bad between them," Somerhalder said.
Without giving away any major spoilers, that woman will be Elena (Nina Dobrev).
Somerhalder did say fans won't be totally against Damon when the show premieres on September 10.
"It's my job to turn him into someone we don't want to see disappear. Beyond his cruelty, he also possesses a lot of charm and doesn't come without a sense of humour, somewhat like Spike in Buffy."