Stein shrugged. "It can be the exceptions that give shape to the rules of science," he said, smiling and hopping up onto the table next to the boy as he spoke.

"The Dark Hour," he mused. "So the shadows could only get out into the world during a certain time. And now the shadows would only be able to get out if that fog were present. There was no fog during this Dark Hour?"

He cocked his head. "And what's an Evoker?"