The Hidden Oracle

The Hidden Oracle is a fantasy novel based on Greek and Roman mythology written by American author Rick Riordan. It was published on May 3, 2016, and is the first book in The Trials of Apollo series, the second spin-off sequel of the Percy Jackson & the Olympians series.

The Hidden Oracle
AuthorRick Riordan
Cover artistJohn Rocco
CountryUnited States
SeriesThe Trials of Apollo (book 1)
PublisherDisney-Hyperion
Media typePrint (hardback, audiobook CD, e-book)
ISBN978-1-4847-3274-8
Preceded byThe Blood of Olympus
(from The Heroes of Olympus) 
Followed byThe Dark Prophecy