Horror Movie is largely about the thin line between reality and artifice, showing that life is just as much shaped by the human acts of construction and revision as it is by the natural forces of the world. The “official” history of the film the characters set out to make is defined by the stories they tell about it and themselves, more than the true story of what happened on set.

The narrator, along with the other characters to a lesser degree, initially presents himself as a blank canvas open for interpretation. Everything from his lack of a given name to the blank clothes he wears is a character detail to be painted over. As soon as the novel starts introducing details about the Thin Kid, the narrative aims to lead the reader to overlay those details onto the narrator, especially considering that the same is done indiscriminately for Cleo, Valentina, and Karson. As the novel unfolds, it becomes clear that this decision leans deliberately into his character arc, which revolves around his transformation into the Thin Kid. The narrator finds solace in imagining what the Thin Kid might think or feel in situations like his sleepover at the abandoned school.