THE VAMPIRE DIARIES Season 3 Episode 19 Heart Of Darkness Sneak Peek : TYLER RETURNS TO MYSTIC FALLS — Elena (Nina Dobrev) and Damon (Ian Somerhalder) set off together to make sure Jeremy (Steven R. McQueen) is safe in Denver, and to see if his special abilities can help reveal the information they need about ancient vampire bloodlines. It doesn’t take them long to learn that Jeremy has been hanging with the wrong people. Stefan (Paul Wesley) and Klaus (Joseph Morgan) both go to brutal extremes in their search for the missing weapon. Caroline (Candice Accola) is thrilled when Tyler (Michael Trevino) returns to town, but Tyler soon suspects that something has been going on between Caroline and Klaus. Matt (Zach Roerig) has his hands full trying to keep Rebecca (Claire Holt) busy organizing the school’s upcoming 1920s Decade Dance. Chris Grismer directed the episode written by Brian Young and Evan Bleiweiss (#319).