In 2475, a bioweapons lab accident releases a virus that kills roughly half of humanity. In the aftermath, Earth itself physically expands to twenty times its original size, all animal life grows to massive proportions, and technology collapses back to pre-industrial levels. The survivors are then introduced to giants — a ten-to-eleven-foot-tall species that had been living hidden beneath the Earth for thousands of years, far more intelligent and long-lived than humans, who emerge to help rebuild civilization on their own terms. Giants establish a technologically advanced society powered by clean energy and a crystal-based economy, with the crystals harvested from megafauna serving as both currency and life-extending medicine. Humans, roughly toddler-sized by comparison, are integrated into this new world not as equals but as beloved companion pets — owned, collared, cared for, and protected by law — living comfortable lives in giant households on a planet that is no longer theirs.