The Tainted Cup by Robert Jackson Bennett
Publication Date: February 6, 2024
Summary from NetGalley:

In Daretana’s greatest mansion, a high imperial officer lies dead—killed, to all appearances, when a tree erupted from his body. Even here at the Empire’s borders, where contagions abound and the blood of the leviathans works strange magical changes, it’s a death both terrifying and impossible.
Assigned to investigate is Ana Dolabra, a detective whose reputation for brilliance is matched only by her eccentricities. Rumor has it that she wears a blindfold at all times, and that she can solve impossible cases without even stepping outside the walls of her home.
At her side is her new assistant, Dinios Kol, magically altered in ways that make him the perfect aide to Ana’s brilliance. Din is at turns scandalized, perplexed, and utterly infuriated by his new superior—but as the case unfolds and he watches Ana’s mind leap from one startling deduction to the next, he must admit that she is, indeed, the Empire’s greatest detective.
As the two close in on a mastermind and uncover a scheme that threatens the Empire itself, Din realizes he’s barely begun to assemble the puzzle that is Ana Dolabra—and wonders how long he’ll be able to keep his own secrets safe from her piercing intellect.

ARC provided by Random House via NetGalley for an honest review.
Confession:
This was a very compelling read that kept me engaged with the characters and the mystery to the very end. The pacing was a bit on the slow side, but I so enjoyed the characters and the world that I ended up not minding the pacing issues as much as I thought I would.
Dinios Kol, or Din, is the sole narrator and a very likable character. His role as an engraver was fascinating, and made him the perfect counterpart to Ana Dolabra. Din doesn’t see himself as smart, due to his lack of reading and writing skills, but he really is quite insightful and sometimes is able to put things together before Ana does. I really liked his relationship with Ana. He really understood her and all of her quirks and helped her navigate society and the murders they were trying to solve. The tagline of it being a Sherlock and Watson type story was very true to form, but I would day that Din was much more astute and observant than Watson ever was. Din does go on a wonderful journey of growth and self discovery in this story and he is such a likable character that you find yourself rooting for him.
The world building was something else entirely. It was more of a science fiction type world than a fantasy one. The way the plants and animals were used to enhance the people of this world was fascinating. The enhancements people took on also had their dark sides and consequences which I am not sure was fully explained to anyone before they took on the changes. Din certainly was unaware of all of the psychological disadvantages of remembering everything would eventually cost him. The society built around this world was also very interesting and tied into the murders quite a bit.
The mystery was well done, with lots clues and twists that kept it all on track and interesting. The way the mystery was presented was also an opportunity for the author to tell us more about this world without a lot of info dumping. There were some tense scenes and some very well written action scenes that kept the narrative flowing. There was also some great dialogue between Din and Ana that showed the growth in their relationship throughout the book. The murder mystery is all tied up by the end of this book, but we are left with enough unanswered questions about the world that will keep us entertained in the next book.
This was an engaging mystery with some wonderful characters and a fascinating new world. If you enjoy books with a lot of world building, engaging characters and a well put together mystery, this is a book you might want to take a chance on.