The Lightning Stones

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 Midwest…