Nancy Perkins (Sandra Harrison) was the protagonist villainess from the 1957 horror film, Blood of Dracula. She was a new student at the Sherwood School for Girls, an all-girls boarding school. She was enrolled there by her father and his new wife, Doris (Nancy's stepmother, who Nancy's father married six weeks after the passing of Nancy's mother), much to Nancy's displeasure. In her first night, she is harassed by her dormmates, led by Myra--who is the assistant to chemistry teacher Miss Branding.
Nancy is recommended by Myra for Miss Branding's experiment, which includes the belief that there is a "terrible power" within humanity that is strong enough to destroy the world. She is later burned by a chemical after Myra and Nola switched them in class, and her angered reaction gained Branding's attention. Nancy meets Miss Branding, who used an amulet from the Carpathian Mountain region to hypnotize her into believing her pain was gone, while also falling under the teacher's control. Later that evening during Nancy's initiation party, Nancy was re-hypnotized from a distance by Miss Branding, and as a result, Nancy transformed into a vampiress. She stalked and followed Nola into the basement after the party was broken up, and it was there that she attacked and killed Nola.
Nancy was woken up by Miss Branding the next morning, with her memory of her actions being wiped clean by the villainous teacher. The next night, during a Halloween scavenger hunt, Nancy approached Terry at a local cemetery, scowling at her while doing so. Nancy turned heel once again and transformed into a vampiress, after which she attacked and killed Terry. After shifting into her human form, Nancy was encountered by Terry's boyfriend, Tab, and backed away from his advances. Shortly afterwards, the evil Nancy transformed yet again and killed Tab, and escaped as the other girls arrived.
By this point, Nancy realizes what was happening to her, but her pleas to Branding were ignored, as Branding had no plans on ending her twisted experiment. Nancy later encountered her boyfriend, Glenn, who was concerned over what was happening at the school. While they were in Glenn's car, the couple engaged in a romantic embrace, but during this moment, Nancy's urge to kill resurfaced. She stopped herself and ran out of the car, and went to Branding's laboratory begging her to be free of the experiment. Branding refused and forced Nancy to look into the amulet again, which transformed Nancy once again. This time, Nancy attacked the villainous Branding and strangled her to death with the amulet's necklace. Before Branding was killed, she shoved Nancy away from her, resulting in Nancy being impaled to death on a broken piece of furniture.