<Tr> <Td_colspan="8"> Harper, the vampire who escaped from the tomb, kills a man in the woods and steals his clothes . Matt and Caroline are surprised by the sudden reappearance of Matt's drifter mother Kelly . Stefan and Elena are worried about Damon's new attitude . Meanwhile, Damon is asked by Sheriff Forbes to take part in a fund - raising bachelor auction and asks the Sheriff for information on Alaric . Alaric discovers that his wife Isobel was Elena's biological mother, and was turned into a vampire by Damon at her own request . He confronts Damon, and the confrontation ends when Damon stabs Alaric to death with a stake . However, Alaric comes back to life, saved by a mysterious ring that Isobel gave him . Elena is determined to find out everything she can about her birth mother, but encounters warnings--possibly from Isobel herself--to stay away . At the end of the episode, it is revealed that Harper will be staying with Anna and Pearl . </Td> </Tr> <Tr> <Th> 16 </Th> <Td> 16 </Td> <Td> "There Goes the Neighborhood" </Td> <Td> Kevin Bray </Td> <Td> Bryan Oh & Andrew Chambliss </Td> <Td> April 1, 2010 (2010 - 04 - 01) </Td> <Td> 2J5015 </Td> <Td> 2.80 </Td> </Tr> <Tr> <Td_colspan="8"> Anna pays a visit to Damon, bringing along her mother Pearl, who wants to take control of the town . All the vampires in the tomb have been released, and most are staying at an old farmhouse on the outskirts of town . Pearl offers to help Damon find Katherine if he helps her out, but the visit turns violent when he turns her down . Meanwhile, Anna arrives unexpectedly at Jeremy's house . Jeremy cuts his hand to tempt Anna, who then sucks his blood, but is interrupted by Jenna . Elena, Stefan, Caroline, and Matt go on an awkward double date to Mystic Grill where Frederick, a now - freed vampire from the tomb, mistakes Elena for Katherine . Kelly, Jenna, and Damon have some drinks at the bar, but Jenna leaves when things start heating up between Damon and Kelly . Frederick and his girlfriend Bethanne, who blame the Salvatore brothers for their entombment, break into the boarding house and attack Stefan and Damon . Stefan stakes Bethanne, but Frederick escapes and returns to the farmhouse, where Pearl punishes him for leaving the house against her orders . At the end, Anna sneaks into Jeremy's room and chastises him for cutting himself in front of her to reveal her secret, but Jeremy insists that he did it because he wants her to turn him . </Td> </Tr> <Tr> <Th> 17 </Th> <Td> 17 </Td> <Td> "Let the Right One In" </Td> <Td> Dennis Smith </Td> <Td> Story by: Brian Young Teleplay by: Julie Plec </Td> <Td> April 8, 2010 (2010 - 04 - 08) </Td> <Td> 2J5016 </Td> <Td> 3.48 </Td> </Tr>

How many episodes in season 1of stranger things