The narrative leaps forward six years, finding the Fearlight family expanded to four with young Morgan, yet emotionally fractured. Max Fearlight’s need for security has deepened; he has severed the bunker’s communications with the outside world and poured his intellect into perfecting the “Echoverse”—a closed-loop digital simulation designed to preserve his family in a digital, risk-free reality. Meanwhile, young Maxine’s restless curiosity leads her to discover a mechanical tracking device, the “Beacon Acorn,” in the garden, confirming her belief that life still thrives in the wasteland. When Sasha’s brother, Jupiter, arrives with a nomadic convoy of Fissionists warning of an impending threat, Max panics, locks down the bunker, and unintentionally seals Maxine outside in the midst of a blinding thermonuclear storm.