Investigative reporter, Warren Getler, the co-author of Shadow of the Sentinel, spoke about an underground Confederate group known as the Knights of the Golden Circle (KGC) that he believes may have buried caches of gold and silver back in the 19th century, that were worth millions. Getler described the KGC as separatists who wanted to protect their own interests in the US (i.e. their agricultural empires), but said they also had roots with European secret societies such as the Knights Templar. In fact, Getler said his book was in some ways, the American version of Holy Blood, Holy Grai, which delved into the mysteries of the powerful Knights Templar in France.

The secret society Skull and Bones was formed around the same time as the KGC, Getler said, and though the two groups did not necessarily share members, he noted that the KGC may have had dealings with Geronimo, whose skull was reportedly acquired by Prescott Bush as a kind of ritual relic for the Skull & Bones group.

Getler said his co-author Bob Brewer deciphered an esoteric KGC code system using pictographs and carved symbols (some resembling those used by the Masons and Rosicrucians) which offered geographic clues as to where some of the KGC treasures were allegedly buried, and that this led him to uncover one cache. Brewer continues to look for clues which can be found carved in trees, stones, and other objects.