
Starting this fall, fans of Rick Riordan's “Percy Jackson” books can discover some adventures that took place at the demigod training facility Camp Half-Blood when Percy himself wasn't around.
Random House Children's Books announced Tuesday that Riordan is collaborating with different co-authors on each of four “Camp Half-Blood” middle-grade novels set during the time between Riordan's first two Percy books, “The Lightning Thief” and “The Sea of Monsters.”