The Dark is Rising Sequence Book #1: Over Sea, Under Stone
by Susan Cooper
Throughout time, the forces of good and evil have battled continuously, maintaining the balance. Whenever evil forces grow too powerful, a champion of good is called to drive them back. Now, with evil's power rising and a champion yet to be found, three siblings find themselves at the center of a mystical war. See also the other books in The Dark Is Rising Sequence.
