In an unknown suburb, children are enjoying a new game called Invasion! with “tremulous joy, such tumbling and hearty screaming” (232). The game is only played by children younger than 10, whose imaginations allow them to take it seriously. Adults see them, “jealous of the fierce energy of the wild tots, tolerantly amused at their flourishing, longing to join in themselves” (233). Mink Morris takes on a leadership role in the game, delegating tasks to the other children. She refuses to let an older boy, Joseph Connors, play, insisting he is too old and threatening to kick him.

Earth, readers learn, is completely at peace. All nations are united in protecting it.

Mink’s mother Mrs. Morris watches the children share how to spell complex words like hexagonal in their game. She demands Mink come in for lunch, which Mink gulps down, eager to get back. Mink claims Invasion! is a matter of life and death—Mrs. Morris remembers how serious everything felt at that age. Mink mentions a friend named Drill, and that Invasion! centers on alien beings invading the Earth, which, according to Drill, is currently “impregnable” (236). Drill told Mink that a surprise attack is necessary, along with securing help from the enemy.