MacDonald and the orangutan Virgil journeyed with Caesar back to the Forbidden City, carrying a Geiger counter and small arms for protection. Discovering the intact (though dilapidated) archives, they scarcely had time to play back a short passage of the "Alien Visitors" (namely, Zira and Cornelius) tape before realising that they had also been discovered – by mutant human survivors of the war. The three barely escaped with their lives, but Caesar now had some insight into who his parents were, and what they knew about future events.