The first book in the series, The Hidden Oracle, was released on May 3, 2016. The second book in the series, The Dark Prophecy, was released on May 2, 2017. The third book in the series, The Burning Maze, was released on May 1, 2018. The fourth book in the series, The Tyrant 's Tomb, will be released in Fall 2019.
when is the 4th trials of apollo coming out
Fall 2019