'He's bringing up a hostage from the back,' she thought. She waited patiently for the voice to get closer, listening to the scuffle as someone was pulled past the bathroom door. Shamira quietly opened the door and grabbed the gunman by both the neck and the wrist. He struggled to keep hold of the little girl that he had grasped against him . . . a little blond-haired girl that clung just as tenaciously to her doll.

In an instant, Shamira took in the surroundings. The RV was obviously not a luxury item for a family traveling across country. It was well worn on every edge, with carpet that looked...