The occult sciences and esotericism were welcomed by a huge enthusiasm in Petersburg at the end of the nineteenth century. On tour in the Russian Empire's capital, British medium Olivia Reed draws large crowds to her public spiritualistic meetings. A sequence of unexplained ritual murders occurs in the city at this time. Girls are kidnapped on the streets, and their mutilated remains are discovered all around the city. Rostov and his subordinate Ganin, a young police investigator, are in charge of the inquiry. Things are becoming more perplexing with each additional victim. In the belief that her true or imagined capacity to conjure the spirits of the dead may help him catch the killer, Rostov turns to Olivia.