We open with a long shot of the McIntyre Ranch in California. Flavia McIntyre (Peggy Converse), and her ranch hands Boyd (James Anderson) and Mike (Charles Horvath) accompany her niece, Jessica (Carolyn Kearney) as she looks for water. Jessica is a water witch and with her divining stick is searching for a new vein of water for the ranch. Three guests arrive on horseback. Gordon (William Reynolds), Linda (Andra Martin) and Hank (Jeffrey Stone) express disbelief and disapproval at Jessica's superstition and childish behavior. Annoyed, Jessica resumes her search for water and finds something. No sooner have Boyd and Mike begun to dig, Jessica changes her mind and admonishes them not to dig as "there's something evil down there." Flavia overrules her niece and orders her ranch hands to continue to dig. Jessica leaves in a huff, but foretells dire consequences. "I hope a tree falls on you." No sooner has she made this pronouncement, when a bough of a nearby tree snaps off and almost kills Linda. They take Linda back to the guest cabins to recover. She wasn't seriously hurt, in her words, "more frightened than hurt." Jessica expresses remorse, but Linda assures her that it wasn't her fault. Jessica is convinced she caused it. Linda asks her about her gift, and Jessica explains she always had the gift to find things: not just water. Gordon, Hank and Linda continue to disbelieve her, so she directs them to where to find Linda's missing watch. She tells them they will find Linda's watch in a trade rat's nest at the base of the old oak tree near Linda's cabin.Gordon, Hank and Linda head for the tree and after a brief search find Linda's watch, which is still working, and something else. They find an old charm that had been buried hundreds of years before, as the tree roots grew around it. They now begin to believe in Jessica's gift. That evening Gordon apologizes to Jessica. Jessica tells him that the voices that direct her searches can sometimes be evil and are hard to resist. Gordon presents the cleaned charm they found to Jessica as a peace offering. Gordon explains the significance of the design and places it around her neck.Gordon goes up to watch Mike and Boyd dig for what they think is a well. They strike something and Mike finds an old chest. He hauls it out of the hole. Flavia is convinced that it contains gold and orders Mike to break it open. Gordon advises against such action. He explains that the chest may be more valuable than the contents, but only if it is not damaged. A preliminary examination shows a date: 1579 and the spelling and lettering is Old English. He can't read much more, and will need to clean it. He tells Flavia that only one Englishman visited that part of California around that date--Sir Francis Drake. Gordon suggests an expert witness be present and tells Flavia he will go over to Berkeley and get the chemicals and Julian Ash, the president of the Historical Society. Flavia is quite perturbed she'll have to wait to see the contents, but agrees. They take the unopened chest back to the main house.It is clear Boyd is in charge and Mike is a little slow witted. Linda invites Jessica to accompany her and Hank to a dance that evening, but Jessica expresses her reluctance. She is hoping Gordon will ask her. As Mike, Boyd and Aunt Flavia approach the house with the chest, Jessica is overcome with a sense of dread. Gordon informs her that he has to leave shortly, but will be back late. Flavia locks the chest in her sewing room and leaves Mike and Boyd to guard it. Jessica tells Aunt Flavia she doesn't want the chest in the house, and won't stay if it does. Linda invites her to stay in her guest cabin. Flavia retires for the night and Jessica goes over to Linda's cabin. Hank and Linda drive off for the dance. As Jessica is trying on some of Linda's clothes, Boyd does a little peeping.Boyd begins to get designs on the chest and its contents and steals the key from Flavia's purse. He talks Mike into tearing open the chest, but instead of gold Mike finds a dirty, withered head (Robin Hughes) that whispers to him. Meanwhile Boyd heads back over to stare at Jessica on the porch. When Boyd returns to check on Mike, he discovers the chest open and Mike behaving very strangely. Boyd pulls a knife on Mike, but is quickly disarmed by the stronger man and is killed. Mike returns to the sewing room to confer with the head, which tells him to hide Boyd's body and take the head outside. All the commotion wakes Flavia and she screams for Jessica to help her. Flavia and Jessica discover the sewing room door open and the chest empty. Jessica notices blood on the floor. Jessica tells Aunt Flavia to contact the police. Mike approaches the house and holds the head up to the window. It reacts to Jessica's charm. Jessica expresses the feeling of something trying to overpower her. Gordon walks in through the open door, accompanied by Julian Ash (Forrest Lewis). Gordon and Julian clean the chest. Gordon suggests that Jessica try to find the wounded ranch hand with her divining stick. They don't realize Boyd is dead and Mike is possessed by the spirit of Gideon Drew.Jessica sets out on her search for the wounded ranch hand. Mike tells Gideon Drew's head about Jessica's gift to find things. Jessica begins to go into a trance and sees the trial of Gideon Drew some 400 years earlier. The judge (Thomas Browne Henry) sentences Drew to death for Satanism. He further decrees that his head and body be buried separately. During the trial the charm or talisman keeps Gideon's power under control. Jessica wakes from her trance and heads back to the house, and finds Boyd's body in the hole dug earlier. The police arrive as Linda and Hank return from the dance. Gordon takes the police to Boyd's body. He suggests that Mike might be the culprit. Gideon's head realizes Mike's usefulness has come to an end and must transfer his influence and control over to Linda. He makes Mike attack the police with Boyd's knife. The police kill Mike. Linda takes the head back to her cabin and places in on a closet shelf. Linda tries to get the charm from Jessica, but is unsuccessful.Gordon, Julian and Flavia meet the next morning. Gordon tells Flavia that the chest only contained a head, and Julian tells Flavia that he believes the casket with the rest of the body is on the ranch property. He wants to find it and will pay Flavia if they can recover it. Linda joins them and suggests they ask Jessica for help. She knows that for Gideon Drew to return to life he needs his body. Jessica joins them. They ask her help, but she refuses. Julian Ash gets the idea that "the gift" is probably inherited and suggests Flavia give it a try. Jessica is angry and goes upstairs to pack. She intends to take the bus to a cousin's house to stay. But before she can leave, Gordon asks her if he can borrow the charm to have a copy made. Gordon removes it, and without her charm Jessica is now vulnerable to Gideon. Linda presents the head in a hat box to Jessica as a going away gift. Jessica is now possessed and her behavior changes radically. Jessica announces she has changed her mind about leaving and will help find the body. Of course, she finds it. They dig up the casket and return it to the house.Jessica retrieves Gideon's head and joins it to the headless body. Gideon Drew is now whole and can move, breathe, and speak. His first order of business is to sate his thirst for blood. He threatens the assembled cast. Gordon tries shooting him with a gun, but it has no effect. Drew can't decide who to kill first. He settles on Gordon, but Gordon has the talisman and repels him with its power. Gordon tosses the charm into the casket Gideon Drew has fallen back into and they close the lid. The spell is broken, and when they open the casket all they find is a skeleton. Gordon retrieves the charm and places it back around Jessica's neck. We close with a close up of the charm on Jessica's ample chest.