6 books • 2 series
Quest for the Holy Grail
The Hunt for Excalibur (Order of the Black Sun, #23)
The Einstein Equation (Order of the Black Sun, #22)
Keepers of the Lost City (Order of the Black Sun, #21)
The Inca Prophecy (Order of the Black Sun, #20)
The Lost Crown of the Knights Templar (Order of the Black Sun, #19)
