In “The Tyrant’s Tomb,” master of middle grade fantasy Rick Riordan continues “The Trials of Apollo” series, the story of Apollo, brought low to earth by his father for a transgression, and made into a very human figure.

As Lester Papadopoulos, acne-ridden and with a waist that is far less than Apollo’s trim figure, Apollo must deal with injury, lack of magic, and insolence. Not to mention mortality. He has come far since the first book in the series on his journey to save the world from a triad of evil Roman emperors, but there’s still a long, dangerous road to travel on this quest.

Along the way, readers are treated to Riordan’s signature humor — often humor which will appeal more to the many adults who will be reading this series than to middle grade readers who will not be able to appreciate some of the clever references (often esoteric musical references) Riordan uses in the narrative. Because the story is told in first person as narrated by Apollo, readers are privy to his innermost thoughts which, of course, are also a great source of humor as Apollo begins the series as an arrogant, selfish and thoughtless god. Readers will appreciate that his character grows throughout the series as without his godlike form, Apollo learns humility and the value of true friendship.

Each chapter starts with a haiku, as Apollo is the god of music, poetry and art. The haikus are funny but also serve to foreshadow the chapter they precede. For example:

“Captain Underpants
Does not appear in this book
Copyright issues”

While the haiku is correct in that Captain Underpants does not appear in the chapter, he is certainly referenced. Other haikus, similarly humorously, give readers a hint of the humor to come.

The pop and literary references never stop. At one point in the story, Apollo’s sidekick Meg boasts that she was permitted to clean the unicorns’ stables. Apollo comments, “She pulled a Tom Sawyer on you.” One can only hope the reference invigorates young readers to want to read Tom Sawyer so that they can understand the reference.

Riordan is expert at combining tragedy with humor and the touching scenes filled with sorrow are lightened by a bit of humor. When Apollo is to lead the funeral of a fallen comrade, he’s not sure he remembers the correct Roman invocation. Riordan has Apollo muse,

“Dearly beloved . . . ? No.
Why is this night different . . . ? No.
Aha.”

Along the journey, readers will meet new characters in this continuation of Percy Jackson’s world and revisit with old friends. Readers will meet characters who are diverse and who — beautifully — reflect the world around us. Some have Hispanic or Asian surnames, another prefers dating someone of the same gender and all have ADHD. (It’s a god/demigod thing.) Some will die and some will miraculously live. Be assured that bad guys will die horrible deaths, and the deaths will be described in horrible, nausea-inducing detail. And also be assured that this is not the end of the series. There is one more emperor to vanquish, and Apollo is on the job.

Start with the first book in the series, “The Trials of Apollo: The Hidden Oracle,” then continue with book two, “The Trials of Apollo: The Dark Prophecy,” and “The Trials of Apollo: The Burning Maze.”

Please note: This review is based on the final, hardcover book provided by Disney-Hyperion, the publisher, for review purposes.