This is the fourth book in the Lost Heroes of Olympus series, so this review will definitely have spoilers for the first three books. It will also have spoilers for the Percy Jackson and the Olympians series, which should be read before the Lost Heroes of Olympus series.
While Percy and Annabeth are suffering their way through Tartarus, the rest of the crew of the Argo II are trying to make their way to the House of Hades, a temple dedicated to Hades that just so happens to also link to the Doors of Death. For Percy and Annabeth to survive, they will have to make their way to the Doors and to stop the monsters from regenerating they will also have to shut the Doors after they have made it inside. A seemingly impossible task, but some beings from the past could be their way to survive or their worst nightmare. Percy must face that he is not the completely nice and unselfish guy that he thought he was and Annabeth must face that she cannot always be the one to control her own destiny. Leo will have to make a difficult choice, love or duty, and Frank will have to embrace his destiny as a son of Mars/Ares. Hazel must learn to use the magic given to her by her mother's blood and Piper learns that to be a true warrior means to see her beauty as the weapon it is. Jason learns to let others lead and that being a true friend is sometimes the best remedy for someone with a broken heart. Poor Nico must reveal his unrequited love and hope for acceptance. The two demigod camps are heading to battle and Reyna must decide if she can trust the Greeks and just how much of herself she can sacrifice. If the group can embrace their flaws they may survive the House of Hades and have a greater chance of saving the world from Gaea.
I think this book could also be entitled "Everybody Loves/Hates Percy." I won't reveal too much, but we do see Percy's main flaw, that he often forgets his friends once the immediate danger is over. He has forgotten Calypso, he forgets the titan Bob, and he finally has to face all those he has killed in a unique and painful way. Riordan makes the characters grow up in this one and that is why the publisher recommended age is a little higher on this one. If you didn't feel sorry for Nico before this book, you will at the end and that is all I will mention or I will give away a pretty big spoiler. I will say I love how the characters matured and dealt with the huge flaws that hang over their heads. This is a great penultimate book and I am kind of afraid of the last book in this series. I am hoping we do not have to say goodbye to anyone of the seven or Nico.
Favorite Character: Hmm, my favorite is kinda of a spoiler, but I won't reveal too much about the situation. Calypso captured my heart in the first series and she does again in this one. Life is so unfair for her. She supported her dad, but she has paid for the support she gave, just let her have someone! I love her transformation in this one and there are two scenes with her in this book that broke my heart! One is an indirectly related scene and the other is with her.
Favorite Quote: "Not giving people a second thought...that can be dangerous." This is pretty much the theme of the entire book, but it is true in life as well.
Riordan's books are always 5 cups of cocoa for me. His writing style is awesome and you grow attached to his characters. I can't believe I have to wait another year for the next and last one in this series!