Trials of Apollo

The Trials of Apollo is an American children's fantasy action-adventure middle grade children's fiction book series based on Greco-Roman classical mythology, written by American author Rick Riordan. It is the third of four book series in the Camp Half-Blood Chronicles, succeeding Percy Jackson & the Olympians and The Heroes of Olympus, and preceding The Nico di Angelo Adventures. A supplementary book, Camp Jupiter Classified, has also been released in addition to the main series. The first book in the series, The Hidden Oracle, was released in 2016. The second book, The Dark Prophecy, was released in 2017. The third book, The Burning Maze, was released in 2018. The fourth book, The Tyrant's Tomb, was released on September 24, 2019. The fifth and final book in the series, The Tower of Nero, was released on October 7, 2020.