In 1925, three children vanish without a trace in Arrowhead Lake. Nearly a century later, there are those who still report seeing the children swimming beneath the surface like elusive dolphins

After losing her husband in a violent car crash, Rachel King and her two young sons venture to Arrowhead Lake to heal. When Rachel discovers that Great Woods Timber is planning to clear-cut this beautiful wilderness, she enlists the help of Lilly Bowman and her mysterious father, chief and shaman of the Wabanaki nation.

But dark events have been set in motion, and Arrowhead Lake is under siege by a sinister force of mercenaries. When Chief Neptune vanishes, Rachel and Lilly call on Seth Ferguson, the local deputy sheriff for help. Together, they discover an astonishing truth; a shadowy cabal that will stop at nothing to obtain the secret of Arrowhead Lake, a secret that if unearthed could have far-reaching consequences.

When one of Rachel's sons vanishes in the Lake, she and Lilly embark on a harrowing journey to find him. What they discover is a mind-boggling truth that will change their lives forever.