On December 10, 1887, a shark fishing boat disappeared. On board the doomed vessel were the Walkers--the ship's captain Frederick, his wife Elizabeth, their three teenage sons, and their dog--along with the ship's crew. The family had spotted a promising fishing location when a terrible storm arose, splitting their vessel in two and leaving those onboard adrift on the perilous sea.

When the castaways awoke the next morning, they discovered they had been washed ashore--on an island inhabited by a large but ragged and emaciated man who introduced himself as Hans. Hans appeared to have been there for a while and could quickly educate the Walkers and their crew on the island's resources. But Hans had a secret . . . and as the Walker family gradually came to learn more, what seemed like a stroke of luck to have the mysterious man's assistance became something ominous, something darker.

Like David Grann and Stacy Schiff, Matthew Pearl unveils one of the most incredible yet little-known historical true stories, and the only known instance in history of an actual family of castaways. Save Our Souls asks us to consider who we might become if we found ourselves trapped on a deserted island.