The third book in the bestselling Percy Jackson and the Olympians series. Now with a new cover look! Discover the story behind the Disney+ series. HALF BOY - HALF GOD - ALL HERO. It's not every day you find yourself in combat with a half-lion, half human... Percy Jackson has a lot on his plate. A powerful goddess has gone missing. The Greek gods are on the brink of war with the Titans. And there's the minor threat of a mystery beast that could destroy Mount Olympus forever. This time, Percy's going to need help and he's found two powerful demigods for the job... There's just the small problem of the prophecy. The one that has predicted not all of them will survive. But when you're the son of a Greek god, it happens. Right?