The ShowstoneMysticism, angels, evil spirits: Harvard Professor Cal Donovan investigates a scrying stone linked to the death of his parents. Algosh, Iraq, 1989. During an archaeological excavation Hiram Donovan uncovers a piece of meticulously knapped obsidian. Instinct tells him to hide it from others on the dig, so he sends it back to his wife in America with a note: John Dee, British Museum Scrying stone? Days later Hiram is murdered with it made to look like