According to Boris Strugatsky's later reminiscences, the Strugatsky brothers were planning to write a sequel to "Inhabited Island". However, following the death of Arkady Strugatsky, the surviving brother felt that he could not bring himself to write the novel. The novel would have been named "White Ferz" ("Белый Ферзь"). Ferz - the Russian term for Queen in chess, which has male gender in Russian. The novel would have followed the story of the infiltration of Maxim Kammerer, now a progressor, into the heart of the Island Empire.