Olive and Violet Bright are off to Blue Cay to solve the mystery of the destruction of the ancient Bimini Road. They meet the legendary race of pirates known as the boucanier who have been living in the Caribbean ever since Columbus dropped them off over 500 years ago. The young sleuths encounter a hurricane, tidal waves, and danger in this former enclave of pirates known as the Purple Sea. The cays are both enchanting and mysterious hiding those hunted by slavers, the Code Noir, and the Spanish Inquisition. Balanced between the rational and the superstitious, the reader is never sure who or what is affecting the fate of the mysterious inhabitants of Blue Cay on the Purple Sea.