What do Scott Peterson, Neil Entwistle and timeless literary seducers epitomized by Don Juan and Casanova have in common? They are charismatic, glib and seductive men who also embody the most dangerous human qualities: a breathtaking callousness, shallowness of emotion and the incapacity to love. In other words, these men are psychopaths. Unfortunately, most psychopaths don't advertise themselves as heartless social predators. They come across as charming, intelligent, romantic and kind. Through their believable "mask of sanity," they lure many of us into their dangerous nets. Dangerous...