Frances McCausland (Erin Chambers), an intelligent and level-headed girl, is starting high school a year early. Strange things have been going on in her town of Middleberg: dogs appearing on people's roofs, alarm clocks going off hours early, eggs all over a teacher's car, gelatin in the school swimming pool, and the letter "B" spray-painted all over town. The Bs also appear on the school lockers—except for Frances', which has a B on the inside. These pranks seem to point to Frances, who does not understand what is happening or why. An older boy named Larry Houdini (Eric "Ty" Hodges II) offers to help Frances, telling her that he is an imaginary friend, which is proven true as children are the only other people who can see him. Larry tells Frances that she is being framed by the Boogeyman. Frances has a difficult time believing this.