There is a quest where lightning has been stolen from Zeus. There also Hades, Helmand has gone missing and Poseidon has claimed Percy as his own. And so people think Percy did it at the recent winter solstice. So Chiron's like, Hey, you got the oracle wants you to go on this quest. You got to get the lightning bolt. And you got to solve this because by the summer solstice, all the gods are going to go to war. And it's going to be war war three.