Macy is an accounting student whose life consists of the kind of routine that makes the minutes feel long and the years feel short — right up until the morning a mysterious firefly arrives. Macy does not follow it. Instead, in her place, a spirit bearing her exact likeness wakes up in Esperanto: a world that has been constructed from the collective dreams and inner lives of everyone who has ever lived. Armed with an explosive broom, this Macy-shaped spirit begins moving through Esperanto looking for its mysteries and looking for home, wherever that turns out to be.