I failed the original novel because it simply was not entertaining, and this is no better. It's the same as the novel so if you came to this via the movie, be prepared for the two to be nothing alike. The movie was significantly better, even though it was average for a movie - and just as racist as this novel.
There is no Gorgon in the novel, which was sad, nor is there a visit to the faux Parthenon in Nashville, and no fight with a hydra. There is no lightning bolt hidden in a shield here, and no wise-cracking Rosario Dawson playing Hades's wife, which was a real highlight in the movie. The final battle isn't between Luke and Percy, but between the token black guy and Percy. Zeus is dressed in a business suit, and in the one single touch I did appreciate, Poseidon is dressed as a surfer dude!
Grover is white in the graphic novel, so I guess they made him black in the movie for no other reason than the one Hollywood always employs: we must have a token black person in this movie so they can't say we're racist. Well guess what, guys - and let me put this in an 'in a world' scenario so you in Hollywood can grasp it - In a world where the vast majority of people are not white, anything that doesn't fairly represent those proportions is racist, period. Get a fucking clue. Even the US is a quarter non-white, so where was that represented in this book? Yeah, you know it.
Every single person in the entire graphic novel was white except for one token villain, who has daughter who was white! I was done right there. This novel sucked and should be boycotted.