Sumara, the head of the criminal investigation department, is investigating the case of a girl who was found covered in snake blood. Coincidentally, the girl is studying archaeology and is conducting excavations at the nearby Podlažice monastery. The magical number 666 was written in blood on her forehead, and her body was wrapped in a snake coiled around an egg. This prompts the involvement of Dr. Runa, an expert in magic and the occult. The incredible mysteries surrounding a satanic cult and the creation of the Devil's Bible begin to unravel.