A Drop of Corruption (2025) by American author Robert Jackson Bennett is the second book in the fantasy mystery series that began with The Tainted Cup (2024). The series name, as of the first book, was advertised as Shadow of the Leviathan; prerelease copies of A Drop of Corruption signaled the title as the second book in this series, but final print versions replaced the series title with “An Ana and Din Mystery.” Penguin Random House, who publishes the series, uses the Shadow of the Leviathan title on their website, as does Bennett on his personal website.

Some readers have speculated that this inconsistency signals Bennett’s intention to write more installments in the series following the success of The Tainted Cup. This would align with conventions of detective fiction, in which series’ eponymous investigators often appear in many loosely related, self-contained mystery stories. In a question-and-answer segment on social media platform Reddit, Bennett reported, “I don’t know how many Leviathan books there will be. More than 3, sure. But 6? 9? 12? You can decide this via dollars, and the buying of them” (“Hello, I Am Author Robert Jackson Bennett. AMA!” Reddit.com, 2019).

Bennett’s series takes place in the Empire of Khanum, a fantasy setting in which vast leviathans, sometimes referred to as titans in the series, annually come ashore from the depths of the sea, leaving destruction in their wake. To combat this threat, the people of Khanum have used the mysterious, transformative properties of the titans’ blood to make “augmentations” and “grafts,” which alter a person’s physical or intellectual capabilities, whether permanently or temporarily. The series’s narrator, Dinios “Din” Kol, has been augmented as an engraver, allowing him to remember every detail of what he sees, hears, and feels with perfect accuracy for the remainder of his life. The series plays with the tradeoffs that citizens of Khanum pay for their augmentations; engravers, like the antagonist in The Tainted Cup, are often driven to extreme mental distress by the weight of their many, often painful memories.

Din and Ana work within the Iudex, one of Khanum’s four military Iyalets, or departments. The other Iyalets are the Apothetikals, or Apoths, who have augmented senses, the Legion, who physically battle the titans, and the Engineers, who build the infrastructure that the Legion deploys against approaching leviathans. The Iudex is responsible for solving crimes and stopping corruption.

Bennett’s world-building style privileges the immersive over the explicitly expository. As Din is a first-person narrator, readers are not given lengthy explanations about the machinations of life in Khanum—which Din, who has lived in the Empire all his life, already knows. Instead, readers are asked to deduce the relevant details as Din encounters them. Thus, while readers do not necessarily need to have read The Tainted Cup to understand the events of A Drop of Corruption, they may find that reading the series in order enhances comprehension, particularly as The Tainted Cup takes place in the Empire itself, while A Drop of Corruption takes place in a politically contested territory outside Khanum’s borders. The Tainted Cup also deals more directly with the threat of the leviathans, something readers may find useful in understanding the stakes of the second installment.

No third book in the series has been announced as of mid-2025, but the open-ended epilogue in A Drop of Corruption suggests that Ana and Din will solve future mysteries together, leaving a possibility for future installments.