The Percy Jackson series was a little hit-and-miss for me. The first book was nearly pitch perfect. It was a fast-paced adventure that managed to be inventive and funny and have interesting characters. With each successive book the story moves further and further into the world of the gods. While this seems like a very logical move storywise, it is why I didn't enjoy the next four books as much as I expect I would.
Part of the charm of the first book was the interaction between the world of the gods and the "real world" or world of mortals. That Percy had one foot firmly in each world made for funny situations. This lessens after the first book.
The Last Olympian pits Percy and the forces of good, which include most of the gods and many of the demigods against the Chronos and his forces, which include many of the lesser gods and also a large number of demigods. The final showdown takes place on the streets of New York City.
The Percy Jackson series started off with a bang. The Lightning Thief was excellent, but the rest of the books were not nearly as good. All in all, the series was just okay. It fell way short of His Dark Materials and Harry Potter.
I saw the teaser for The Lightning Thief before the latest Harry Potter movie. It looked cool. I expect that the movies will do well.
My review of The Lightning Thief (Book One)
My review of The Sea of Monsters (Book Two)
My review of The Titan's Curse (Book Three)
My review of The Battle of the Labyrinth (Book Four)