Sparrow Thibault is drawn inexorably to the waters of the deep, flowing Arizona Canal during a summer thunderstorm. There, she is struck by a bolt of lightning, and when she awakens, she hears a disembodied voice telling her something she cannot believe--something astonishing and wonderful.

The revelation sends her on a dangerous journey to escape those who believe in the voice’s prophecy: a darker, stranger force, desperate to stop her from the realization of her destiny. Accompanying her is a renegade priest, Father Patrick Kilian, who struggles against his own dark forces.