The narrator is an ordinary man who fails to understand basic figurative language. He mistakenly believes he has discovered an alien invasion by taking the idioms in a discarded pulp novel literally. Prone to paranoia and isolation, he reacts to his perceived discoveries with visceral physical fear before ultimately retreating into passivity rather than taking action.

The narrator's wife is an ordinary woman spending time in the family home. She notices her husband's audible gasp while he reads and asks him what is wrong. Unaware of his paranoid thoughts about extraterrestrials, she accepts his dismissive lie and returns to her evening activities.

The narrator's children are present in the house while their father experiences his paranoid episode. They focus entirely on playing a board game. Their normal, everyday activity happens right beside their father's fearful internal monologue, and the game ultimately offers him an escape from his panic.

Julia is a character in the pulp novel the narrator reads. The book describes her "blushing and knitting her brows angrily" or "giving her heart" to a young man. Because the narrator reads these common idioms as literal physical events, her fictional actions directly trigger his panic about alien biology.