THE VAMPIRE DIARIES Season 4 Episode 6 We All Go a Little Mad Sometimes Sneak Peek : ELENA’S NEW NIGHTMARE — Terrifying hallucinations leave Elena (Nina Dobrev) shaken and confused, causing her to make a dangerous mistake. After giving Stefan (Paul Wesley) some very disturbing news about Elena, Klaus (Joseph Morgan) takes matters into his own hands. Professor Shane (guest star David Alpay) reveals a story of ancient witchcraft to Damon (Ian Somerhalder) and Bonnie (Kat Graham). With help from Klaus and Stefan, Jeremy (Steven R. McQueen) begins a new chapter in his life. Finally, Elena makes a painful personal confession to Stefan, and Matt (Zach Roerig) gives Damon startling new information about Professor Shane. Wendy Stanzler directed the episode written by Evan Bleiweiss & Julie Plec (#406).