Sequel to Avengers of Olympus After hearing that Tartarus had taken Percy, all the demigods had tried to find a way to get him back.They knew he had sworn on the River Styx so they couldn't break that promise. Annabeth Chase had seemed to be stronger than ever. She fought better, thought better and led better. She had been preparing for a showdown with Tartarus to get Percy back. When Annabeth finds a way across the problem she realizes only one person can help her. And she knows that no favor can be free in their world. How far will Annabeth go to get Percy back? What will be the cost? Disclaimer- I do not own Percy Jackson and those characters or the Avengers.