Geologist and adventurer Philip Mercer is visiting an old friend who’s working far down in Minnesota’s Leister Deep Mine-but he arrives too late to save Abe Jacobs and his climate-research team from a shocking, brutal attack. Mercer vows to seek revenge as well as answers, hoping to pick up Jacobs’s search for a cache of the rare crystals known as lightning stones-rumored to have been aboard Amelia Earhart’s plane when it vanished in 1937.

From a harrowing close call in the Midwestern U.S. to a nailbiting showdown in the rugged mountains of Afghanistan, to a remote island in the middle of the Pacific, Mercer must race to stay ahead of a team of highly-trained assassins-and to figure out if he’s chasing a rare scientific discovery, or merely a historical fairy tale.