The Vampire Diaries Season 2 Episode 17: Know Thy Enemy

The Vampire Diaries Season 2 Episode 17 can be watched on Thursday on April 7, 2011 at 8:00pm EDT on WPIX (CW) TV channel. Title of the brand new episode is: Know Thy Enemy. Synopsis of the episode is: Isobel unexpectedly returns, leaving Jenna devastated and causing both Elena and Alaric to lash out at John. A heartbroken Caroline tries to figure out what to do about Matt, while Stefan and Damon realise they have a new weapon.