In the early days of the 20th century, an entire team disappeared while on an expedition deep into the Grand Canyon in search of a long-rumored hidden city.

Set in the Grand Canyon, a team of Smithsonian researchers have stumbled across a lost walled Aztec city guarded by some evil spirits, including a "great flying serpent of death." As days turn to weeks, Susan Jordan, the daughter of the professor leading the expedition, assembles a team to rescue her father and his colleagues from the clutches of the ancient Aztec warriors and their horrible serpent god.—Anonymous