Hark, Who Comes? Haunted or Hoax : Season 1 Episode 28

Casey researches ancient curses while Jac tries to help Ellia. Casey and Jac find out which curse has been used and Jac goes looking for the paper it's been inscribed on. Ellia ends up going into the kitchen and Casey follows her, trying to figure out what she's doing. Ellia warns Casey to stay back, but it's too late; Ellia becomes possessed by the ghost of Lady Grantham.