Ok. I need to know the name of this movie. It looks like its set in the late 1800's and made in the 70's and it centers around this brother and sister who drink this liquor or potion of sorts in a graveyard. Then everything spins around and they fall on the ground and go in the past where they meet a young man and girl who live or work in a run down 1800's mansion with a disgusting and abusive housekeeper. Originally the house was burned to the ground and the young man and girl get burned to death but the intervention of the brother and sister changes the past and they live.