In 1979, Marcia Grady has put her high school and college cheerleading days behind her. Having graduate from college, the sexy blonde is now a rookie cop. The always ambitious Marcia wants to be a detective and knows a big bust will get her that job. Pam Grady is Marcia's young sister and has been in her shadow as long as she can remember. Her jealousy had now turned to hate and a real desire for revenge. The young Grady starts to plot against her sister. The creepy old man just up the street appears to be just what both sisters are looking for.