In Rick Riordan's The Lightning Thief, first novel of the series titled "Percy Jackson and the Olympians," the story begins to turn when Percy discusses his dream with Annabeth, a dream about a voice from a pit asking Percy to help him rise. Percy had thought the voice was the voice of Hades but now has his doubts. In fact, Percy begins to doubt that Hades is the one who took Zeus's lightening rod.
The story truly turns after the three heroes make their way into the underworld. There, the magical, flying shoes Luke gave to Percy, who in turn gave them to Grover since flight is Zeus's realm, take flight and drag Grover toward a pit. Percy recognizes the pit as the one the Olympian gods buried Kronos, god of the Titans in, after the war between the gods. Percy then recognizes the voice from the pit in his dream as coming from Kronos, not Hades, and that it is Kronos who has aspirations of rising from the pit to regain power. Further, he learns it was Kronos who somehow had the lightening rod, not Hades.