After the defeat of the Circle of Eighteen uprising, the Black Squad is still in the service of the sinister Mistress and continues, moving through the Empire, to finish off the small surviving rebel groups. One day, the detachment goes north, to Juniper, to a strange city, to an unknown land lying outside the empire of the Lady with an order to explore the unfinished fortress, which the locals call the Black Castle. Grotesque, alien to man architecture. Unimaginable monsters grin from the walls, and giant snakes are frozen in crusts on the towers. The castle is growing continuously. And when it reaches the required size, its inhabitants will be able to free the Mistress's husband and the former ruler of the Empire - the Lord. If this happens, then an even more powerful Evil will appear to the world than the Ten Taken. But this is not included in the plans of the Lady. Therefore, the Black Squad must destroy the castle, but no one can be sure that they can handle this terrible battle.