An old man named Charlie is awoken from being cryogenically frozen and meets Kit, a Tour Guide to the Future. Kit has been specially chosen and trained for this job by the Allocator, an AI that runs and helps humans/intelligent life survive and flourish in this futuristic world. Charlie is confused and upset by this development, but consents to entering a simulation. The first one, chosen by Kit, is a Bird Simulation, that terrifies Charlie. The next one is chosen by Charlie, and it is a 'perfect' Middle Earth world, inspired by Lord of the Rings.

Kit and Charlie stay in the Middle Earth world for nearly a decade, but it eventually bores Charlie, so Kit pulls them out and they spend a year in the Bird Simulation. At the end of this, they speak with the Allocator again, who reveals his master plan. Charlie has asked to do something to benefit humanity, to be productive somehow, and Allocator asks him to go on an expedition, past the solar system and Allocator's influence, to explore and judge the condition of other planets for human habitation. Charlie immediately agrees, but Kit objects, realizing that Allocator had manipulated Charlie into this decision for his own gain. Still, Charlie ends up going, and Kit is distraught with the realization that Allocator has manipulated them both. But after seeing a nearly empty hanger of ships, she realizes that this is not the first time that this whole sequence has occurred, far from it. Her memory of it will be erased again, yet Kit understands that she continues to do this because she wants the best for humanity.