In 2045, immortality has become a reality. Now people can be digitized, after which they acquire a potentially endless life in the form of virtual Copies. Some people manage their own company after death, some want to give their dying mother eternal life, and some are hiding in the new reality from the sins of the past. There is only one caveat: your life depends on the stability of the global computer network. And they might just erase you. And therefore, when a strange man named Paul Durham comes to the powers that be, who have already gone into virtuality, and talks about the City of Permutations, a refuge where Copies will not depend on the real world, many jump at the opportunity to gain true immortality. But who is he? Paul Durham? An ordinary madman, a clever swindler or a brilliant visionary? His clients do not yet know that the City of Permutations touches on the deep properties of the Universe and opens up truly unimaginable prospects for the development of all humanity. But the promised paradise can turn into a nightmare, and the ideal refuge may already have other owners.