Sylvie and Jules, Jules and Sylvie. Better than just sisters, better than best friends, they’d be identical twins if only they’d been born in the same year. And if only Sylvie wasn’t such a fast runner. But Sylvie is too fast, and when she runs to the river they’re not supposed to go anywhere near to throw a wish rock just before the school bus comes on a snowy morning, she runs so fast that no one sees what happens…and no one ever sees her again. Jules is devastated, but she refuses to believe what all the others believe, that, like their mother, her sister is gone forever. At the very same time, in the shadow world, a shadow fox is born --- half of the spirit world, half of the animal world. She too is fast and she senses danger.