Here's a quick rundown: Eve and John continue their exploration of Earth-like planets within the U-2 universe. John remains committed to selecting worlds at various stages of development, eager to observe evolution in action—watching geology, flora, and fauna unfold over time. His ultimate goal is to witness the pinnacle of evolutionary development: the emergence of man. Ignoring the so-called experts and their definitive pronouncements of absolute knowledge—of which John knows they are lacking—he and Eve use Eve's Interactive Reality system to explore the planets. This technology translates data received from scanning arrays into visual and tactile experiences, allowing them to observe and feel firsthand how life is truly evolving on those worlds.

However, John begins to suspect that, despite the wondrous sensations the IR system offers, its use comes at a cost—one extracted through painful, potentially deadly mishaps. Incidents he believes are being triggered by the IR system and deliberately targeted at him.

Eve, however, sees things differently. She presents what she believes is a more reasonable and plausible explanation: these incidents are simply natural reactions to planetary conditions, not evidence of malicious manipulation by her system.

Their disagreement intensifies, becoming a deepening point of contention. Eve demands proof of John's theory; without it, she makes it clear she will never accept his conclusions. This leaves John with a perilous challenge. She has placed the burden on him to resolve the conflict. Yet the proof he needs can only be obtained by continuing to use the IR system—raising two critical questions: Can John survive its use long enough to uncover the truth? And more urgently, can they survive each other—this clash of perspectives—their mutual stubbornness—their absolute belief that only one of them is right, and the other irrevocably wrong?