In the race to save one of their own, Sigma Force must wrestle with the deepest spiritual mysteries of mankind in this mind-expanding adventure from the #1 New York TimesMalleus Maleficarum, the Hammer of Witches. What they uncover hidden deep in the past will reveal a frightening truth in the present and a future on the brink of annihilation, and force them to confront the ultimate question: What does it mean to have a soul?