The Heroes of Olympus is Rick Riordan's sequel series to the Percy Jackson and the Olympians series. It focuses on Greek-Roman mythology instead of only Greek mythology like its predecessor series. The sequel series to it is The Trials of Apollo.
"Seven half-bloods shall answer the call,
To storm or fire, the world must fall.
An oath to keep with a final breath,
And foes bear arms to the Doors of Death!"
The Seven Heroes of Olympus
- Percy Jackson: Greek demigod and son of Poseidon.
- Annabeth Chase: Greek demigod and daughter of Athena.
- Piper McLean: Greek demigod and daughter of Aphrodite.
- Leo Valdez: Greek demigod and son of Hephaestus
- Jason Grace: Roman demigod and son of Jupiter .
- Hazel Levesque: Roman demigod and daughter of Pluto.
- Frank Zhang: Roman demigod and son of Mars and legacy of Poseidon.
- The Lost Hero – October 12, 2010
- The Son of Neptune – October 4, 2011
- The Mark of Athena – October 2, 2012
- The House of Hades – October 8, 2013
- The Blood of Olympus – October 7, 2014
- The Demigod Diaries - August 14, 2012
- The Lost Hero was made available as an audiobook read by Joshua Swanson on October 12, 2010, with a play length of 16 hours and 34 minutes.
- The Son of Neptune was made available as an audiobook, read by Joshua Swanson, on October 11, 2011 (a week after the release of the book), with a play length of 13 hours and 27 minutes.
- The Mark of Athena was made available as an audiobook read by Joshua Swanson on October 2, 2012, with a play length of 15 hours and 9 minutes.
- Two Giants have appeared in each book except the Blood of Olympus.
- The Lost Hero is the only book in the series where one of the two giants that appears in the book lives.
- The Son of Neptune is the only book in which Leo and Piper do not narrate a chapter.
- The House of Hades is the only book in which all members of the Seven recieves a chapter in their point of view.
- The Blood of Olympus is the only book where several giants appear within the same book. They are Porphyrion, Polybotes, Orion, Mimas, Thoon, Hippolytos, Enceladus, Periboia, Otis and Ephialtes.
- From The Son of Neptune onwards, each character received four chapters in their point of view.
- The Heroes of Olympus series is the only series in the Percy Jackson franchise to not be written in the first person narrative format, instead being written in the third-person format.
- Unlike the Percy Jackson series, there are no chapter titles in The Heroes of Olympus books. Instead, Roman numerals are used, a nod to the addition of its mythology in the series.