I started reading book four in the Dark Olympus series a few days ago. By this point, I've learned that the series is fairly formulaic. The leads are forced to be together. Then each book has it's own spin on the kind of romance. Finally, all of that is set within a broader narrative of what is happening in the city of Olympus. It's entirely predictable but it works. I will read this series until the very last book.
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