The Potency of Ungovernable Impulses (The Investigations of Mossa and Pleiti, #3) by Malka Ann Older Format: eARC
Source: supplied by publisher via Edelweiss
Formats available: hardcover, ebook, audiobook
Genres: climate fiction, gaslamp, mystery, science fiction, science fiction mystery, space opera, steampunk
Series: Investigations of Mossa & Pleiti #3
Pages: 246
Published by Tor Books on June 10, 2025
Purchasing Info: Author's Website, Publisher's Website, Amazon, Barnes & Noble, Kobo, Bookshop.org, Better World Books
Goodreads
The Hugo and Nebula nominated science fiction detective series continues with The Potency of Ungovernable Impulses, featuring a new mystery concerning alarming incidents of targeted, escalating academic sabotage.
When a former classmate begs Pleiti for help on behalf of her cousin―who’s up for a prestigious academic position at a rival Jovian university but has been accused of plagiarism on the eve of her defense―Pleiti agrees to travel alongside her and investigate the matter.
Even if she has to do it without Mossa, her partner in more ways than one. Even if she’s still reeling from Mossa’s sudden isolation and bewildering rejection.
Yet what appears to be a case of an attempted reputational smearing devolves into something decidedly more dangerous―and possibly deadly.
My Review:
The first two Investigations of Mossa & Pleiti, The Mimicking of Known Successes and The Imposition of Unnecessary Obstacles, both began with missing persons cases rather than the corpse that kicks off most mysteries.
This third entry ALSO begins with a missing person, but not in the same way – at all. In the earlier books, the missing persons WERE the mystery, where this time the missing person is the person who usually investigates the mystery. Not that it’s not mysteries all the way down from the human-settled platforms that circle Giant (AKA Jupiter) to the roiling surface of that gas giant of a planet.
But Mossa is the person who is missing, sorta/kinda, and Pleiti is definitely the person who is missing her. (Not that THAT hasn’t happened before in their relationship!)
Mossa is lost, not physically but emotionally, deep in a depression that is so endemic to the human colony on Giant that it has a name and a pathology of its very own. Pleiti, on the other hand, is just a bit lost, leaving her partner behind in order to take a long trip around the transport rings to Stortellen, the university that sees itself as the rival of Pleiti’s own institution, Valdegeld.
Because a friend is being threatened, and she needs Mossa and Pleiti to investigate. If all she’s going to get is Pleiti, that’s going to have to do.
And it does – even if it doesn’t do at all for Pleiti herself until it’s nearly too late.
Escape Rating B: Part of what made the first two books in this series work so well, and made them so much fun to get into, was the way that Investigator Mossa and Scholar Pleiti balance each other out, both in personality and skill set. Not that they aren’t both capable in their own fields, but rather that the mystery usually involves tackling a puzzle that straddles both specialties and they need each other to reach the solution.
Neither of them can see the forest for the trees, as that saying goes, but they can each see the forest for the other’s trees, and when needed, the other way around.
This time around, Pleiti leaves Mossa behind to help out a friend – at Mossa’s seemingly indifferent behest – then feels guilt-ridden because she didn’t recognize her lover’s depression. But she’s stuck, and stuck in, and has to make the best of the situation no matter how deeply she feels like an imposter.
It should work, because the case is very strongly rooted in Pleiti’s personal bailiwick. It’s a story about academic reputations, the fragility thereof, and the ease and rapidity with which an unfounded rumor can derail an entire career. It’s steeped in the maliciously incestuous incivility of the worst of academe, and it’s an environment that Pleiti, as a scholar herself, knows all too well.
But without Mossa, Pleiti flails and angsts a LOT. Not that the situation doesn’t warrant both, and not that she doesn’t wish for Mossa’s ability to obtain an actual, legal, warrant when needed, but mostly she needs Mossa’s pragmatism and laser-focus to balance her out.
I have to say that, as much as I wanted to slip back into Mossa and Pleiti’s world, and as much as I enjoy them as characters and find their setting fascinating, this entry in the series didn’t work for me as well as the first two.
There were a few reasons for that. One is the obvious as stated above, they are better together than they are separately. With Pleiti as the first-person narrator, combined with her tendency to angst-spiral, it sometimes got a bit hard to take.
And that’s on top of the deep dive into the darker corners of bad behavior in academe, of which there was a lot and I have to say that the motives for the reputation bashing were a bit opaque and off-the-wall at the same time. I did figure out whodunnit, but their reasons for doing it mostly get chalked up to ‘ungovernable impulses’.
Also, because of the way this story was deep into the academic life, AND because English or whatever common language has evolved over the decades if not centuries on Jupiter, that language used has gone out and mugged a whole lot of other languages for words, to the point where I kept dropping out of the story to get a translation for a word that I was almost but not quite sure of in context. My immersion in the story got broken OFTEN, and I don’t believe this was the case in the previous books, but without Mossa it seemed that Pleiti got deep into the jargon and cliches and colloquialism of her own profession to the exclusion of those not a part of it. Which is exactly what kind of insider-speak is intended to do, but it frequently lost this member of the intended audience.
Your reading mileage may vary.
I still like Mossa and Pleiti, especially when they’re together, so I’m still following this series. Based on the ending of this book, this sapphic, gaslamp, SF mystery is planning to go full Sherlock Holmes in the next book, with Investigator Mossa striking out on her own as Giant’s first PRIVATE investigator and presumably, hopefully, Pleiti as her Watson-esq chronicler.
I’m looking forward to finding out!
