Wearing just a nightgown, Jessica [Zohra Lambert] sits in a rowboat, staring at the water. "I sit here, and I can't believe that it happened," she says to herself, "and yet I have to believe it. Dreams or nightmares? Madness or sanity? I don't know which is which."Backing up a few weeks, Jessica has just been released from six months in a mental institution. In order to protect her from the stresses of NYC, husband Duncan [Garton Heyman] has given up his job as celloist for the New YorkPhilharmonic and purchased the old Bishop farm on Brookfield Island, Connecticut. When he, Jessica, and their hippy friend Woody [Kevin O'Connor] arrive at the tall, white, almost-gothic country home, they are surprised to find apale, mysterious, red-haired woman already living there. Her name is Emily [Mariclare Costello], and she is simply a drifter using the house because she thought it was abandoned, she tells them. When Emily offers to move on, however, Jessica invites her to have dinner with them and stay the night. Emily happily agrees. After dinner, Emily entertains on her lute while Duncan accompanies on his cello. Then, Emily engages Jessica in a seance to call up any spirits that might have died in the house. Unfortunately (or maybe fortunately), none show up.One night moves into more nights, and Emily continues to stay. It's becoming obvious that Woody is attracted to her, and Jessica doesn't mind having Emily around, especially because Jessica has begun hearing voices and seeing a blonde girl [Gretchen Corbett] looking at her and then disappearing. Another time, her leg was grabbed by someone under the water in the cove where she was swimming. Jessica is afraid to talk about these things with Duncan or Woody lest they think she's relapsing.Soon, Jessica becomes aware of other problems. 1) Duncan also appears to be attracted to Emily, 2) the men in town, all of whom are bandaged in some way or another, seem to be hostile towards them, and 3) money is tight. To get money for food, Duncan and Jessica decide to sell off some of the antiques they find around the farm. One of the items is a silver-framed portrait of the Bishop family -- father, mother, and daughter Abigail. Sam Dorker [Alan Manson], ex New Yorker and antique dealer, offers them $50 for the frame and tells them the story of how 20-year old Abigail Bishop drowned in 1880 just before her wedding day. Legend says that she's still alive, roving the island as a vampire. Jessica finds the story fascinating, but Duncan just wants to take the money and go home.After returning to the farm, Jessica and Duncan go for a walk around their property. Emily is sitting on the front porch playing her lute, and Woody is out spraying the apple trees. Jessica finds a mole and Duncan offers to take it back to the house and put it in a jar while Jessica stays in the graveyard to do some grave rubbings. She is just about to do a rubbing of Abigail Bishop's grave when she notices the blonde girl beckoning her to follow. The girl leads Jessica to a cliff, at the bottom of which lies Sam Dorker dead and bloodied. By the time Jessica finds Duncan, however, the body is gone. Did she really see it? The look on Duncan's face says that he thinks Jessica is going nuts again. Just then, Jessica notices the blonde girl standing on the cliff above them. Duncan sees her, too, and gives chase. He catches her, but when Jessica tries to ask her questions, the girl is either mute or won't talk. Suddenly, Emily walks up, and the girl runs off.That evening at dinner, it's obvious even to Woody that Duncan and Emily have eyes for each other. When Jessica retires early, Woody tells Duncan to take care of his wife. Reluctantly, Duncan goes up to their bedroom. Instead of taking care of his wife, however, he tells Jessica that she needs to return to New York to see her doctor again. Jessica becomes upset and tells Duncan that she wants to sleep apart tonight, so Duncan goes down to sleep on the couch where he is easily seduced by Emily.The next morning, Jessica finds the little mole has been repeatedly stabbed to death. Jessica denies doing it, but Duncan decides that it's time to get help for her and drives into town in search of a phone. While he's gone, Jessica goes up to the attic where she is surprised to come face to face with the silver-framed portrait of the Bishop family that they had sold just yesterday to Sam Dorker. When she takes a look at the three figures in the portait, she is astounded to see how closely Abigail Bishop resembles Emily. Is it possible they are one and the same?Suddenly, Jessica sees Emily coming up the stairs. Jessica tries to keep her cool while Emily denies that she is Abigail, all the while she is stroking Jessica's feverish face. Finally, out of a desire to get safely out of the attic, Jessica agrees to go with Emily for a cool swim in the lake, even though she's afraid of the water after being grabbed at the other day. As the two women sit at the end of the dock, Emily rubs suntan lotion on Jessica. Suddenly, Emily pushes Jessica into the water and jumps in after her. When Jessica panics, Emily apologizes for scaring her when all she wanted to do was have a little fun. Jessica wades towards shore and looks back to see that Emily has disappeared. She hears Emily's voice in her head and then sees her reddish-hair bobbing to the surface. When a pale white arm grabs her and tries to pull her underwater, Jessica fights to break loose and return to shore. She looks back at the water and watches Emily, pale and dressed in Abigail's wedding gown, rising slowlyfrom the water and walking towards her, all the while silently saying, "Stay, Jessica, stay. Follow me."When Emily reaches Jessica and tries to bite her neck, Jessica's bravado returns. She runs back to the house, locks herself in her room, and waits for Duncan to return. Hours pass, during which Jessica can hear Emily's voice whispering to her. "I'm still here... I won't go away... you can't get rid of me... I'm in your blood... you want to die." Come 5 PM and Duncan still hasn't returned, so Jessica changes out of her swimming suit and hitches a ride into town. While Jessica is on her way to town, Woody returns from working the fields to find that the only one at home is Emily. Although Woody doesn't like how Emily has been playing Duncan, he readily submits when she comes on to him. He gets a bite in the neck for his reward.When Jessica gets into town, she sees Duncan's car and asks about his whereabouts, but none of the men will admit to having seen him. Jessica notices that every man has cuts on his body and backs away... straight into the arms of Sam Dorker. Now totally confused about her own sanity, she runs back toward the farm. When she can run no more, she collapses on the ground and lies there until it turns dark and she hears Duncan calling her name. Duncan drives her the rest of the way home, and they go upstairs to bed. As they begin to kiss, Jessica notices a cut on Duncan's neck. Jessica tries to convince herself that it's only in her mind, but then she sees Emily brandishing a carving knife and leading the men from town. Jessica leaps from the bed and runs outside, knocking over Duncan's cello case to see the bloody body of a little girl come tumbling out.Jessica keeps on running. Along the way, she sees Woody's sprayer but when she gets closer, she sees Woody lying on the seat, his neck cut and bloody. She keeps on running. Around daybreak, she makes it to the ferry and tries to board, but the ferryman tells her, "The ferry isn't running for you." Jessica jumps into a nearby rowboat and begins paddling out into the lake. Suddenly she sees a hand reach into the boat from the water. She stabs the person in the back several times with a long pick. As the body floats away, pale and bloody, she sees that it is Duncan. Back on the shore, Emily/Abigail and the men from town can be seen watching her."I sit here, and I can't believe that it happened," Jessica says to herself, "and yet I have to believe it. Nightmares or dreams? Madness or sanity? I don't know which is which."[Original Synopsis by bj_kuehl.]
Output: Question: Who does Jessica stab?, Answer: Duncan