Book 4 (Book 1: The Lost Hero, Book 2: Son of Poseidon, Book 3: Mark of Athena)
At the conclusion of The Mark of Athena, Annabeth and Percy tumble into a pit leading straight to the Underworld. The other five demigods have to put aside their grief and follow Percy’s instructions to find the mortal side of the Doors of Death. If they can fight their way through the Gaea’s forces, and Percy and Annabeth can survive the House of Hades, then the Seven will be able to seal the Doors both sides and prevent the giants from raising Gaea. But, Leo wonders, if the Doors are sealed, how will Percy and Annabeth be able to escape?
They have no choice. If the demigods don’t succeed, Gaea’s armies will never die. They have no time. In about a month, the Romans will march on Camp Half-Blood. The stakes are higher than ever in this adventure that dives into the depths of Tartarus
This was a great book. The book is really split into two perspectives: one is the journey of Leo, Frank, Jason, Piper, and Hazel accompanied by Coach Hedge and Nico as they go to Greece to the doors of death on earth’s side and then there is the perspective of Annabeth and Percy as they journey through Tartarus to the doors of death. There was no book specific prophecy and it mainly was a set up for the major Prophecy of Seven and the final book. I liked what they did with Leo’s character since they made him more than just a comic relief. They gave him depth by giving him a romantic interest and his demigod abilities to create all kinds of devices was impressive. For Frank he definitely stepped up as a son of Ares, conquering his fears and becoming a leader. Surprisingly I felt like Jason didn’t do too much in this book which was a bit disappointing because Jason and Percy are sort of top dogs. Jason did finally come to realize that he isn’t exactly all Roman would leads me to believe by the end of the series there will be a serious blending of the two groups. His moment with Nico was interesting. Piper also didn’t do too much but it looks like she’ll be fighting ready when the time comes. Hazel got a lot of attention since as a daughter of Hades there was her connection with Nico and since her mother was a witch she has other talents she can rely on. Nico didn’t get his own point of view but you definitely get a lot more background. In Tartarus Percy and Annabeth have only each other to rely on as you can definitely feel the love but sometimes it felt too much. Annabeth kept going on about how Percy and herself has gone through so much to not be split apart now, which sure is true but she constantly is saying it. They don’t really encounter many monster challenges as I was expecting but instead it was the very environment that was against them. They do meet some surprising allies along the way. The whole Roman camp vs. Greek camp was always in the background but nothing definitive outcome came out of it yet.
The final book in the Percy Jackson/ Heroes of Olympus series is called Blood of Olympus and comes out Fall 2014.