This book studies Los Angeles County and its government since World War II. A special focus is given to the "Titans of Temple Street," the five-member Board of Supervisors that determines policies and actions for many issues throughout the county, especially for residents who do not live in the county's 88 cities. It is the largest of all U.S. counties, with a population of more than 10 million, more residents than 41 states, and an annual budget of more than $44 billion, more than all but 19 states. It has served as an innovative example of county government since the early 1900s.

In this third book of the acclaimed series, Percy and his friends are escorting two new half-bloods safely to camp when they are intercepted by a manticore and learn that the goddess Artemis has been kidnapped.

Caught in the middle of an ancient power struggle, Emily and Pegasus must venture to Diamond Head volcano in Hawaii to track down the one thing that can save Olympus--before the Titans get there first.