"After angering his father Zeus, the god Apollo is cast down from Olympus. He must learn to survive in the modern world until he can somehow find a way to regain Zeus's favor"--
After learning that the father he never knew is Poseidon, God of the Sea, Percy Jackson is transferred from boarding school to Camp Half-Blood, a summer camp for demigods, and becomes involved in a quest to prevent a war between the gods.
The Greek god Apollo, cast down to earth as the ungifted human teenager Lester Papadopoulos, and his demigod friends must go through the Labyrinth to find the third emperor--and an Oracle who speaks in word puzzles--somewhere in the American Southwest.