They’re our neighbors, friends, colleagues, and family members. We interact with them daily, even as they manipulate, lie, cheat, and steal, all without showing empathy or remorse. They’re not quite psychopaths, but they’re not quite right, either. Something about them is just a little bit off — and they can make our lives a living hell. In a new book, excerpted here, two local experts take us inside the world of these hidden predators.