Of the three main young adult series I have read (Twilight and Potter being the other two), Riordan’s is faster paced, funnier and brings out more history/mythology than the other two. Very enjoyable and highly recommended to adults and kids alike. As with the other two series, the Percy Jackson series should be read in order. (Lightning Thief, Sea of Monsters, Titan’s Curse)
With Thalia (daughter of Zeus) joining Artemis and the Hunters at the end of book #3, Percy (son of Poseidon) has a new concern with the discovery at the end of book #3 that Nico is the son of Hades. Though he was apparently born before the agreement between the ‘big three’ (Zeus, Poseidon, Hades) to have no more offspring, he and his now dead sister Bianca’s past is vague and unknown to them.
The campers/heroes of Camp Half-Blood know that Kronos’ army (led by Luke, son of Hermes and ex-camper) will attack, probably through the Labyrinth, created thousands of years ago by Daedalus. During a camp game of capture the flag, Percy and Annabeth stumble upon an unknown entrance to the Labyrinth that is inside the Camp’s protective barrier. Since Annabeth, as a daughter of Athena, has studied the architecture and the architect, she is chosen by the Oracle to lead the quest to find Daedalus and enlist his aid against the impending invasion.
Grover (the satyr and Percy’s best bud) is given one last chance to find the god Pan by the “Council of Cloven Elders”, and he believes Pan is hiding in the Labyrinth. Therefore Grover also joins the quest. Together they go into the Labyrinth to enlist Daedalus help.
Riordan’s books are a ‘Who’s Who’ of Greek mythology, bringing in Titans, Olympians, Lesser Gods and mythological creatures at every turn. He also includes mortals who can discern things in the magic realm, like Percy’s mother and like Rachel Dare, who helped Percy in book 3 and is called upon again in book 4. He also uses dreams as communication vehicles to tell parts of the story from other perspectives, and this weaves together the disparate storylines.
Riordan is also building excellent momentum with his stories, as he adds heroes (Nico), Titans and Olympians to the mix, as well as prophecies about the coming war between the Olympians and the Titans and Percy’s role in the battle. He also increases the tension between Annabeth and Percy, as they both get older and other rivals (Luke, Rachel, etc.) come between them.