Once the private place of worship for Sansevero family, and then transformed into their burial chapel, this church museum holds some very strange and astounding objects.

It was under the eccentric hand of Raimondo di Sangro, the Prince of Sansevero, that the Cappella Sansevero began to form the collection it has today. The head of the Neapolitan Masonic lodge, Raimondo di Sangro was a true Renaissance man, an ardent disciple of the sciences, practitioner of alchemy, a mystic, inventor, and polyglot.

The prince spoke numerous languages including Arabic and Hebrew, and invented, among other wonders, a hydraulic device, an "eternal flame" using chemical compounds of his own invention, and a carriage with wooden horses which, apparently, could travel on both land and water.

To the townsfolk, this all seemed a bit...dark wizardish. A "black legend" arose about the prince and local rumors flew that the prince could create blood out of nothing, that he was a Rosicrucian (as a Mason, he was close enough), and that he had people killed to carry out his dark experiments. (It only added to his dark reputation that a grisly murder, with which the prince had nothing to do, took place in his family home.)

Ignoring the speculation on his evil ways, the prince went about his business collecting an interesting set of artistic and scientific objects. Among these were two "anatomical machines" showing a man and a pregnant woman. (There was once an anatomical fetus displayed as well, but it was stolen from the museum.) Built on real human skeletons, these fleshless bodies represent the veins, arteries, and musculature in amazing detail. Long thought to be made by an early form of plastination, they were recently discovered to be made—with the exception of the human skeletons—of beeswax, iron wire, and silk.

The anatomical "Adam and Eve" were made by anatomist Giuseppe Salerno and were meant to illustrate the viscera and arterial systems of human beings. But they also furthered the "black legend" around the prince, and many believed that the prince had two of his servants killed to use their bodies in the construction of the models.

Other interesting objects in the Crypt include the sculptures "Veiled Truth" and the "Veiled Christ." The "Veiled Christ" is a particularly bizarre looking sculpture, made from marble, which distinctly resembles Han Solo encased in Carbonite. The Veiled Christ inspired a number of its own "black legends" including that the Prince had invented a process for the “marblization” of real human bodies.

Between the family crypt covered in masonic symbols, the anatomical machines, and the unnerving "veiled" sculptures, it is not difficult to understand why the Prince was surrounded by a "black legend." Then again, this may have been just how the mysterious alchemist Prince wanted it.