DANCING WITH DANGER — As the high school prepares to throw a "1960s Decade Dance," Elena starts receiving disturbing messages from Klaus via an unusual source. Bonnie tries to reassure Jeremy that she is strong enough to help Elena, but a worried Jeremy asks Stefan for advice. Caroline talks Matt into taking her to the dance. Expecting Klaus to show up at the dance, Damon and Alaric attend as chaperones, but Klaus is playing a complicated game that keeps them on edge. Finally, Damon comes up with a new plan of action that shocks and upsets everyone.