Nico di Angelo and Will Solace. Disney-Hyperion After planting that story seed in The Tower of Nero and conceiving a new book from Nico's perspective, Riordan decided he couldn't do it alone.

The next book in the Percy Jackson universe, which for the first time will be co-written by Riordan and collaborator Mark Oshiro, will focus on the son of Hades and his boyfriend, the son of Apollo.