IN the end it was the cold that drove Anna. She couldn’t stay any longer staring at the bodies: the man who had died for her and the woman she’d killed. But it was the cold, leaching the heat from her body that gave her the impetus to move.

Wearily, she got to her feet, disturbing the wolves who were piled around her in the futile effort to keep her warm. She looked apologetically at Charles. “I know the cars are only a couple of hours away—can you show me how to get there?” She looked at the corpses and then back to Charles. “I can’t stay here anymore.”

With...