plot of Percy Jackson & the Olympians: Lightning thief
Lord kronos will overthrow the gods and bring back the Golden Age.
Stop this Luke, you are being brainwashed.
The trio escape Hades and find Ares at the beach. Ares had cooperated with the thief that stole the lightning bolt and the helm of darkness. Percy duels Ares and later wins and gains the helm which he returned to the owner. Then he returns the bolt to Zeus.
Luke confesses to Percy that he stole the master bolt and helm of darkness. Luke works for the titan Kronos and they plan on overthrowing the gods. Luke leaves camp half-blood and Percy decides to go back home and attend camp during summer.