Vespers Rising - Scholastic, and Riordan, Rick, and Lerangis, Peter

Fourteen-year-old Amy Cahill and her younger brother Dan thought they could return to their regular lives when they found the 39 clues. But the Vespers, powerful enemies, will stop at nothing to get the clues. And with the Vespers rising, the world is in jeopardy.

Vespers Rising 2011, Scholastic Press, New York

ISBN-13: 9780545290593