I really don't know whether to give this three or four stars.
On the one hand, the first few chapters dragged. They were a tad boring and it took some time to get into the story. Also, Cassandra didn't have much of a personality. I could't connect with her. And Apollo/Aidan irritated the crap out of me. He's super overprotective of Cassandra. You'll see when you read it.
Yet the action picked up very quickly and after the first 50 pages, I soon had a vested interest in the story. And Athena was a very interesting character. I really enjoyed her chapters. And Hermes was pretty funny.
And, of course, how can you go wrong with Greek Mythology? When I was little, I was very interested in it, but sort of forgot about it as the years passed. Antigoddess restored my interest in it.
So overall an enjoyable read. Push past the first few chapters and you'll have a gripping and entertaining story.