In the long-awaited prequel to the popular book series by Yulia Yakovleva, readers learn about the return of the first Russian hussars to Moscow after Napoleon’s army left in 1812. Rotmistr Murin and his companions discover a half-ruined mansion from which a piercing scream can be heard in French. After entering the mansion, an explosion occurs that knocks Murin unconscious. Later, he finds the body of a woman and realizes that what happened was a planned attack. Now he must solve the riddle behind this attack and determine whether the explosion caused the woman’s death.