You've parked your carry-on luggage in the overhead bin and glanced at the diagrams stuffed in the elastic pouch, so it's time to stretch your legs and make the usual inquiries. What do you do when you find out that the attractive woman sitting next to you on this flight to Texas is a murderer? A murderer? In these pricey clothes, with this perfect manicure and sophisticated speech? Do you ask to change seats?

Rainbow Blackman, rocking uneasily between titillation and terror on this turbulent trip, keeps her seat and tries to keep her cool, but they're scarcely off the ground before she...