Having received a luxurious diamond necklace as a gift from her guardian Cardinal Armando Albizzi, Louise Fernanda very soon realized: now her life had turned into an escape from... death. The girl's four friends, also generously gifted by the cardinal, were killed one after another. A little later it was Armando’s turn. Louise was left an orphan for the second time. And the culprits of all her terrible losses are precious stones marked with some mysterious numbers. Perhaps this is a code, but to unravel it, you need to get all the stones, including those that are now in the hands of the killers...