The historical center of the ancient city of Veliky Guslyar is under attack - it was decided to demolish several architectural monuments for the construction of a high-speed highway. Preserving the appearance of the city can only be a miracle or... the invention of the anti-gravity method of transferring buildings Professor Mintz sends Cornelia Udalov into a parallel reality to his doppelganger, who has succeeded in solving the problem of gravity. You will learn about the adventures of Cornelius in the well-to-do native Guslyar and his deteriorated copy from the story “Perpendicular World” and other stories of the collection ..