The history of the Jesuit state, founded in 1610 on the territory of Paraguay and which existed for one hundred and fifty years, has been little studied. However, from the works of the monks that have come down to us, it is clear that the Jesuit missionaries also sought to acquire cultural values and artifacts of the Indians. They fearlessly went to abandoned Indian cities in order to penetrate their secrets, including the secret of the crystal skulls. The novel examines one of the versions of the appearance of these skulls in South America and their purpose.