Dark Shadows - Season 12 Episode 24 : DS-1223 1971

Morgan appears to be possessed, but will not reveal who he is. Melanie asks Julia about her real parents; Julia tells her they are dead. Melanie finds a letter that indicates her real mother might still be alive, Julia takes the letter and burns it. Morgan goes to the cottage and demands that Carrie give him the key to the basement; Carrie goes into a trance and later realizes that Morgan is possessed by James Forsythe.