On this edition of ST, we speak by phone with John Geiger, the bestselling author of "The Third Man Factor" and "Frozen in Time," among other books. A member of the editorial board of the Toronto Globe and Mail, Geiger is, moreover, a fellow of the Explorers Club and the chair of the Royal Canadian Geographical Society's Expeditions Committee. He joins us to discuss his new book, "The Angel Effect," which The Wall Street Journal calls "highly readable [and] often gripping." It's book that explores the surprisingly common occurance of people being visited by an otherworldly presence in times of great danger or desperation --- or, as a critic for Kirkus Reviews put it, this book is "an intelligent rendering of a chilling phenomenon." If what we call "angels" do, indeed, exist, as Geiger supposes today on our program, perhaps they are the by-products of the human brain...rather than heaven-sent messengers in flowing white robes. In detailing the vivid and myriad of accounts of people who report being aided by the "angel effect" as they confronted various crises --- from physical abuse and sexual assault to automobile accidents and airplane crashes --- this book reveals compelling discoveries about our complex and ever-more-mysterious brain --- and about our innate capacity to hope.