Heir to the Underworld by JB Dennis shows promise with its extensive cast and deeply complex source material, even if it struggles to juggle them all at once.

Fourteen young adults find themselves locked together in a room with fourteen Olympian gods. Once it gets a little too crowded, they leave with divine powers given to them by their respective patrons.

From then on, they train to master their new abilities, learn about their respective domains, and eventually become immortal.

From the beginning, the author gives not-so-subtle hints as to which god the heirs are replacing. Benjamin Darke, for instance, dresses in primarily black attire and is appropriately mentored by Hades.

Other obvious character matches include sports champion Andrew St. Cloud and bossy Ashley Queen, the replacements for Zeus and Hera respectively.

Heir to the Underworld is an impressive display of the author’s considerable knowledge of Greek mythology. The mythical gods and creatures encountered are well-researched, and I found myself learning something new about them every few pages.

It’s very apparent Dennis has a passion for mythology in general, which many writers understand as crucial for successful world-building. There is a colossal amount of potential to further explore the different realms and their conflicts.

Aside from some formatting issues, my main concern was that the sizable cast of characters seemed to overwhelm the plot. It seemed as if every character needed to say or do something so that you didn’t forget they were there, rather than because the plot called for it.

I would have liked a more solid conflict as well. A familiar foe appears towards the end to shake things up, but by then there’s been little to no build up.

All in all, Heir to the Underworld has loads of potential. JB Dennis obviously has an immense amount of knowledge when it comes to Greek mythology, and I await to see what new shenanigans the heirs get into as the series progresses.