[1] Along with Meg McCaffrey, he journeys to the Oracle of Trophonius in Indianapolis and later settles his personal feud with Commodus, the second Emperor of the Triumvirate Holdings.

Their adopted daughter Georgina went missing after searching for the Oracle of Trophonius to receive a prophecy to prevent the Emperor Commodus from taking their griffins.

Britomartis, the goddess of nets and owner of the Waystation, issues Apollo and Calypso a quest to rescue the griffins stolen by Commodus.

Apollo, Leo, and Meg head to Commodus's lair and free all the captured animals and prisoners, including Georgina.

They take everyone back to the Waystation, where Georgina relays a recorded message instead of a prophecy by Trophonius, who is revealed to be Apollo's son.

At the Oracle, Apollo drinks from both the River of Memory and of Forgetfulness to prepare himself for taking the prophecy, but which also makes him lose his sanity for the time being.

Apollo finds Commodus fighting Josephine, Calypso, Lit, and Thalia while holding Leo, Hemithea, and Georgina hostage.

Meg reveals a prophecy in the form of a Shakespearan sonnet, which tells them that they must warn Camp Jupiter of an attack in five days and will have to travel in the Labyrinth with the assistance of a satyr.

[2] There once was a god named ApolloWho plunged in a cave, blue and hollowUpon a three seaterThe bronze fire eaterWas forced death and madness to swallow The Dark Prophecy was announced on Rick Riordan's website on May 5, 2016, two days after the release of The Hidden Oracle.

The cover, illustrated by John Rocco, was revealed on December 22, 2016;[5] featuring Apollo along with battle ostriches and a pair of gryphons.

[16] In the United Kingdom and Australia, English-language editions in hardcover, paperback, ebook and audiobook were also released on May 2 by Puffin Books.

[17] To date, editions have been released in Spanish, Italian, Polish, Portuguese, Bulgarian, Dutch, French, Czech, Turkish, Norwegian, Albanian, Hebrew, Catalan and Vietnamese.

Preeja Aravind of The Free Press Journal opined that the book appeals to Riordan's already established fantasy, with the old characters showing development.

Carrie R. Wheadon of Common Sense Media praises the addition of characters such as the ex-immortal couple Emmie and Jo as a way to increase depth.

[14] Pamela Kramer, former National Book Reviewer for Examiner.com, praised the characterization of Apollo as well, calling him "the brightest sun of all."

Wheadon of Common Sense Media criticizes the fast-paced action, stating that it causes the reader to forget important details.

[35] The novel was nominated for Best Middle Grade & Children's Book of 2017 in the Goodreads Choice Awards, and ended in second place, behind The Ship of the Dead, also written by Riordan.