The sun and the star

A Nico di Angelo Adventure, commonly known as The Sun and the Star, is a 2023 American children's fantasy action-adventure middle grade children's fiction novel based on Greek-Roman classical mythology co-written by American authors Rick Riordan and Mark Oshiro. The book is a sequel to the 2020 novel The Tower of Nero in The Trials of Apollo series, and is the first book in The Nico di Angelo Adventures series. The novel follows the demigod children and boyfriends Nico di Angelo and Will Solace, the sons of the Greek Gods Hades and Apollo, respectively, as the boys follow a prophecy on a quest into the deep dark abyss of Tartarus, underneath the Greek underworld, to rescue an old friend of the boys, commonly known as Bob, who is, in fact, the Greek Titan Iapetus.