New York police detective Aldous Fowler faces a difficult case. A successful neurologist, Dr. Katie Hart, has been found dead, with a mysterious word fire-branded on her palm and her skull somehow completely empty. After getting recruited by FBI Lt. Tessa Taylor to help their investigation, Aldous learns that a series of men of science are being murdered throughout United States. The only common factor seems to be their past in the Cornell University.
At the same time, 15-year-old Nicholas Kilby and Beth Hampton discover their own mystery through their membership to a special private project to train future astronauts. The two teenagers are sucked into an online videogame where Carol Ramsey, a virtual woman claiming to work for their foundation, reveals they have been chosen to solve a challenge connected to the Essence of the Mystery.
Their respective stories will became tangled by the dark hand of a secret guild of millonaires, the Gothic Club, whose true intentions seem more sinister than anyone can imagine.
The novel was followed in 2009 by a proper sequel to Grimpow, named Grimpow and the Witch of the Lineage, which takes action back to the Middle Ages again.
The book contains examples of:
- Aerith and Bob: As typical for Ábalos, some surnames are real (Taylor, Fowler, Hart), while others are just Anglo-Saxon sounding made up words (Bladock, Seik, Drester, Murliken).
- Artistic License – History: Kogan's whole predicament is a rather significant Plot Hole. The Gothic Club places him in a "Truman Show" Plot where they pretend him to be a heretic living in the Middle Ages and being judged by the Catholic Inquisition, yet when he tries to argument this is all a charade, it never occurs to him to point out the most obvious: that his captors must be speaking to him in some late form of English instead of historically-accurate Old French or Medieval Latin, otherwise he would be just plain unable to understand them. Unless he's still drugged in some magical narcotic that impeded him from realizing this while leaving the rest of his functions intacts, this is an oddity never addressed.
- Artistic License – Linguistics:
- Forensics technician Scrinn A. Kendall is purportedly nicknamed Scrinna. This would work in Ábalos' original Spanish language, where the letter A is pronounced as in the English "ah", but not in the English language the characters are supposed to be speaking, as the English pronounciation would make the nickname Scrinnay instead. (Don't think much about it, though - the character is based on Ábalos' real life friend Francisco Escriña, so you can guess why did he do this.)
- Kogan is unable to recognize Latin language while hearing a church chant, only deducing it due to its sonority. Although it is possible that it is actually mock-Latin done to mess with his head (or again, that he's subtletly drugged), it's still bizarre that an astrophysicist like Kogan would be that unfamiliar with a language whose terms are used in many modern sciences, especially in the Anglosphere.
- Artistic License – Religion: The Yin-Yang symbol comes from Chinese Taoism, not Indian Hinduism as Professor Bloom claims. The fact that the character is supposed to be a symbology expert only makes it even more blatant.
- Bittersweet Ending: Surprisingly for a young adult-ish book, the ending barely avoids being a full fledged Downer Ending. By the end, Stuck is dead, and Nicholas and Beth complete the game and are inducted into the Universe Foundation as they were meant to. However, Benson and the rest of the Gothic Club are still free and active, and it turns out Nicholas is the new vessel of Grosling's mind. Practically speaking, this means the villains have finally put their hands on the Essence of the Mystery, without anyone in the Foundation realizing, and are closer to get their goals than ever.
- Body Surf: Grosling and Hart build a sort of mind scanner that allows them to copy and implant entire minds. This is actually more akin to creating mind-clones, but they both treat it this way.
- Continuity Snarl:
- It turns out the Essence of the Mystery is actually something Beth can identify as a modern computer chip made of a mysterious material, despite the first book had described it as being smooth and almond-shaped, not flat and carved like one would imagine. The sequel Grimpow and the Witch of the Lineage, which was written after this book, doesn't mention it had an unusual shape either.
- Grimpow had established the owners of the Essence of the Mystery don't leave corpses behind when they die, instead vanishing in thin air. In this book, however, we get to see Grimpow's tomb, and it isn't implied or suggested that it is empty. Another owner of the stone, Kenneth Kogan, gets burned to death in this very book, and he also leaves very physical ashes behind. It's possible that there is some devil in the details, possibly that it stops working if the owner has succesfully passed the stone to another person, but if this is the case, it's never explicitly said.
- Happy Ending Override: To a point. This book reveals that Grimpow died young, possibly not much after the events of its own book.
- Hypocrite: The Gothic Club's creed claims they will liberate mankind from technology... just after proclaiming that their new secret technology which allow them to reign supreme.
- Last-Name Basis: Lieuetenant Taylor's first name is only revealed well into the story.
