So, The Heroes of Olympus. It’s the second series based on the idea that all of the Greek (and now Roman) myths were true. The gods/demigods/et al live in the ‘center of the Western world’ (read: America). It’s actually a really neat idea and a really neat world. It turns out, those old myths are really weird.
But herein lies the main problem I had with The Lost Hero. We’ve already been there / done this. The Lightning Thief did it and did it better. If you only read one of the two, I would honestly suggest that one. On the other hand, if you loved the Percy Jackson books and want to read more? You could do far worse.