Divine Ruin

Sister Holiday Mystery #3

by Margot Douaihy

In the latest in the USA Today bestselling, award-winning, critically acclaimed series, New Orleans punk rock nun-detective Sister Holiday plunges into a “hellish underworld of drug trafficking, addiction, and her own dark past in a journey that is both riveting and sacred.” (Ana Reyes, New York Times bestselling author of The House in the Pines )

“ Divine Ruin is fearlessly inspired.” (Gillian Flynn)

It’s a steamy, restless end of the school year in New Orleans. Sister Holiday is finishing her music classes and preparing for her permanent vow ceremony, a pivotal moment in her journey of faith. But when one of her favorite students is found dead of a fentanyl overdose, Sister Holiday and her partner-in-PI, Magnolia Riveaux, are determined to track down the drug dealers. As students continue to fall prey to this sinister drug, Sister Holiday becomes more desperate to stop the epidemic—while facing her own past with addiction, a demon that is never too far.

With Douaihy’s signature mix of grit, heart, and faith, Divine Ruin tests the limits of Sister Holiday’s devotion in her darkest and most shocking case yet.

Genres: Mystery, Addiction, Thriller, Queer, LGBT, Mystery Thriller

Audible Audio

Published January 13, 2026

About the author

Margot Douaihy (b. Scranton, PA) lives and works in Northampton, MA. She earned a BA in Writing from the University of Pittsburgh and a PhD in Creative Writing from Lancaster University.

Douaihy is the author of the lyrical crime novel SCORCHED GRACE (Gillian Flynn Books), which was named a Best Crime Novel of 2023 by The New York Times, The Guardian, Apple Books, CrimeReads, Barnes & Noble, & Novel Suspects, among others. The second book in the Sister Holiday Mystery series, BLESSED WATER, was named a Best Crime Novel of 2024 by the New York Times and the winner of a Publishing Triangle Award for LGBTQ Crime Fiction. DIVINE RUIN, the third installment, publishes January 13, 2026. Margot is also the author of Bandit/Queen: The Runaway Story of Belle Starr, a true-crime poetry project, and Scranton Lace, a documentary poetry collection about the life and death of a lace factory.

A Co-Editor of the Cambridge University Press Elements in Crime Narrative Series and Multimodal/Multimedia Section Editor of Journal of Creative Writing Studies (RIT ScholarWorks), Douaihy’s work has been featured or reviewed in Colorado Review, The Florida Review, North American Review, PBS NewsHour, Mystery Tribune, Portland Review, Vanity Fair, Vulture, and others.

Douaihy serves as an Assistant Professor with Emerson College.

Honors include the Saints & Sinners LGBTQ+ Festival Emerging Writer Award (2024); Pinckley Prize for Crime Fiction, Best Debut Mystery (2023); Left Coast Crime Best Debut Mystery Nominee (2023); Best Author by Boston Magazine (2023); The F. Lamott Belin Arts Scholarship for Virtual Reality Poetry (2023); Massachusetts Book Award Longlist (2023); New England Book Award Finalist (2023), Mass Cultural Council Artist Fellowship (2022), The Florida Review Humboldt Poetry Prize Runner-Up (2021), Ernest Hemingway Foundation Hemingway Shorts Finalist (2021), and Lambda Literary Award Poetry Finalist (2015).

A founding member of the Creative Writing Studies Organization and an active member of the Association of Writers & Writing Programs, Queer Crime Writers, and Radius of Arab American Writers (RAWI), Douaihy is represented by United Agents, Laura Macdougall (literary) and Jennifer Thomas (screen).

Reviews

[Sam]

This is book two in a series, I haven’t read the first instalment and I definitely feel like I missed something.
You could go ahead and read this one without having read the first book, like I did, but I recommend reading book 1 first.i feel like that will give you information you need on the origins of these characters.

A tatted up lesbian nun? I mean, what’s not to like? Maybe all the religious stuff and the “nunning”, but that’s personal.
I feel like there is a lot of repetition in this story, mostly when it comes to describing a character, not about how they look, but what they do. Business partners and friends are frequently described with the same adjectives as used not 2 or 3 pages before, sometimes even a couple lines before. That’s the kinda stuff that irks me.
Other than that it’s a decent story, I enjoyed the PI stuff and the friendships. Must say I didn’t guess the bad guy right, which is great.

[Hannah · Rating 5 out of 5]

If sister Holiday has million fans, then I'm one of them.
If sister holiday has one fan, then I'm THAT ONE.
If sister holiday has no fans, that means I'm dead

The TWISTS!!! The prose!!!! The YEARNING. The Drugs. The BonTon!!!!!

Everyone should be reading this series. It’s maturing like a fine wine.

Thanks for the ARC. I literally have never been more excited to get one.

[Juliana · Rating 4 out of 5]

I haven't ever been one for detective books. I think mystery is fun but I never found myself really feeling a connection to the detective character outside of them being some uber smart know-it-all who figures out the mystery without any of the clues somehow. And that's why I really love Sister Holiday; she's flawed and vulnerable, raw and real to the point that can at times make you cringe and wish she hadn't done that exact thing. This paired with Douaihy’s writing makes these books feel so intriguing and fun for me! I love the unconventional setting and the way the element of each book is woven into the narrative so cleanly. I've met Douaihy before, as she's good friends with one of my undergraduate creative writing professors, and she is just as witty and real in person as you would expect and it translates so well into her writing. I'm so glad I got to read this ARC and continue following Sister Holiday and her twists and turns through being a queer punk nun.

[Shannon · Rating 3 out of 5]

Not sure it was my fav of the series but I still enjoyed this third cozy mystery set in New Orleans following amateur detective and queer nun, Sister Holiday. She's flawed and funny, has a crush on her coworker and gets caught up trying to solve who's behind supplying fentanyl to one of her students who overdosed. Many thanks to NetGalley and the publisher for an early digital copy in exchange for my honest review.

CW: addiction, drug overdose

[Robin · Rating 4 out of 5]

It's the last couple of weeks of the school term, and Sister Holiday is preoccupied with preparing for her final vows, when one of her students dies of a fentanyl overdose at school. Devastated and passionately determined to find out where the drug came from and protect her students, Holiday enlists her PI partner, Riveaux, to dig around for the source of the drugs. Then she is asked to go undercover for the police, facing temptation from her old demons, as well as danger from the drug gang. Douaihy's language and imagery bring us right into sultry New Orleans, and the story ramps up the tension until the final scenes. My favorite Sister Holiday yet!

[Tina · Rating 4 out of 5]

Divine Ruin by Margot Douaihy
#fifthbookof2026 #arc #divineruin #sisterholiday #bookthree

CW: death, murder, drug overdoses, drug use, drug trafficking, reference to animal abuse

From Netgalley: It’s a steamy, restless end of the school year in New Orleans. Sister Holiday is finishing her music classes and preparing for her permanent vow ceremony, a pivotal moment in her journey of faith. But when one of her favorite students is found dead of a fentanyl overdose, Sister Holiday and her partner-in-PI, Magnolia Riveaux, are determined to track down the drug dealers. As students continue to fall prey tothis sinister drug, Sister Holiday becomes more desperate to stop the epidemic—while facing her own past with addiction, a demon that is never too far. With Douaihy’s signature mix of grit, heart, and faith, Divine Ruin tests the limits of Sister Holiday’s devotion in her darkest and most shocking case yet.

My thoughts: This is book three in a series I have really been enjoying. Anything set in New Orleans is a win for me, and I have grown to love Sister Holiday. And I was both devastated for her, then overjoyed for her in just a matter of pages. Her struggles with faith and sobriety are universal and relevant, and I can’t wait to see what she gets up to next. These stories are gritty and engaging, and I’m really drawn to them in a visceral way. Looking forward to book four!

Thank you to @zandoprojects Gillian Flynn Books and @netgalley for the advance copy. (Pub date is 1/13/26)

[Jan · Rating 5 out of 5]

Sister Holiday, our favorite tattooed queer punk rock nun detective is back, teaching guitar to highschoolers and just being her bad/good self in NOLA. But then it all goes to perdition when a good solid student of hers dies of an overdose right in front of her and she is unable to make a difference. She and her PI partner, Magnolia Riveaux, are now on a mission to track down the drug dealers. She and her own addiction history are working the case when her nemesis on NOPD taps her for a bit of undercover work with the same goal. It gets pretty dicey, and it is a never ending battle. The nun who has "been there, done that" can and does get right in there and does the best she can while fighting her own demons and praying her way through it all.
Hope 2027 will bring us Book 3!
Laissez les bons temps rouler!
I requested and received a temporary uncorrected review e-proof from Zando Projects | Gillian Flynn Books via NetGalley. Pub Date Jan 13 2026 #preorder ebook, print, audio
#DivineRuin by Margot Douaihy @neonmargot #SisterHolidayMysteriesBk3 @thegillianflynn @zandoprojects #NetGalley
#LGBTQCrimeFiction #NOLA #opioiddeaths #drugtrafficking #nun #NOPD #undercover #addiction #crimenarrative #testsoffaith #personalloss #grieving

[Mary · Rating 4 out of 5]

Perfect for current and former queer Catholics, Divine Ruin combines mystery with musings of being a queer catholic. This is Margot Douaihy's third book in her Sister Holiday mystery series. The main character, Sister Holiday, is novice nun, preparing to take her final vows. Oh, and she's a lesbian with a dirty mouth and serious vices. As Sister Holiday is preparing for her vows to become an official nun, the school the Sisters of the Sublime Blood run is hit with a series of fentanyl ODs. While grappling with her own history of addiction, Sister Holiday and her co-private investigator, Magnolia Riveaux take on the case to find out who the supplier is. Consistent with her prior two Sister Holiday books, Douaihy spent her time building a rich mystery that does not shy away from challenging social topics. This book had me hooked with beautiful descriptions of horrible circumstances. Douaihy highlights systemic challenges with poverty, addiction, and being a queer Catholic that will resonate with many readers.

[Taylor · Rating 4 out of 5]

First of all, let's talk about this cover -- perfection!

I am glad I kept going back to this series after being disappointed in the first one because third book in and I really feel like we've found Sister Holiday's voice. Her jaded sarcasm & witty one-liners are so funny and brilliant that it more than made up for the parts where the plot itself seemed to drag.

In this third installment, our badass nun must go undercover to try and track down a fentanyl dealer that has infiltrated her school and is causing harm to her students. Her character is filled with so many wonderful contradictions that it makes for a fun ride!

Thanks to Netgalley and the publisher for the ARC in exchange for my honest review.

[Miranda · Rating 3 out of 5]

This is really well written. The prose is sharp, gritty, and sometimes even beautiful. There’s a strong sense of place, and Sister Holiday is a compelling character to follow. That said, the pacing felt a little off. Some parts dragged, others moved too quickly, and I kept waiting for it to click into place in a more satisfying way.
I also didn’t realize this was part of a series. It can technically be read on its own, but it definitely feels like you're missing some important context. There are character dynamics and emotional beats that probably work better if you’ve read the earlier books, but they didn’t fully land for me without that background.
Overall, I liked parts of it and can see the appeal, but it didn’t fully come together for me.

Thanks NetGalley for the ARC!

[Paloma · Rating 5 out of 5]

Sister Holiday is facing one of her hardest cases to date. One of her favorite students, Fleur Benoit, is found dead from an apparent fentanyl overdose. It is up to Sister Holiday to dig deep into what happened to Fleur in the most unconventional ways.

I've been a Sister Holiday fan since book one. She is flawed, brilliant, witty, dark, and a great human being. I enjoy her ramblings and afterthoughts. Her opinions are strong and she always has something to say. But she is also very active and imperfect which made her such a great candidate to go undercover. She knows right from wrong though sometimes she has to fight hard against her past demons. I love her character so much.
Thank you Netgalley and Zando Projects for this eARC. All opinions are entirely my own.

[Cassanova33 · Rating 3 out of 5]

This was gearing up to be my favorite installment in the series. Great writing, great character work, great read. But something incredibly disappointing happens near the end that kind of ruined the whole thing for me. Not only did it play into what I consider to be a harmful trope, but narratively, it was a quick and definitive end to what was a complex and interesting character dilemma, one that I had hoped would continue further into the series. Four stars for 90% of the book, two stars for the last 10, so I’m splitting the difference.

[Kiera Murphy · Rating 5 out of 5]

Thank you to NetGalley for this ARC!

What a firecracker book to round off Sister Holiday’s adventures. Bouncing back between anger, betrayal, sadness, grief and almost everything in between this character development of Sister Holiday truly meant everything to me. The writing as always is impeccable and absolutely gorgeous, this truly had me hanging onto every last word! An incredibly easily rated 5 star read and if this is the last we see of Sister Holiday, as gutted as I’ll be, at least she went out with a bang.

[Rainy · Rating 4 out of 5]

Thank you NetGalley and Gillian Flynn Books for this ARC in exchange for my honest opinion.

The cover caught my eye and then I saw lesbian, tattooed, nun and I was ready! I haven't read the first two in the series (I've since bought them) I think this can be read as a standalone. I love her sarcasm and one liners. I enjoyed the mystery aspect as well.

[Jim · Rating 4 out of 5]

Margot Douaihy’s Divine Ruin is likely to be one of my favorite mysteries of 2026. The city is New Orleans and nun-detective Sister Holiday is looking into overdoses at the catholic high school. Memorable characters and a good whodunnit. I can’t wait to go read the prior entries in the series. It is available Tuesday.

Published in 2026

Grade: A-

[Chelsea · Rating 4 out of 5]

Sister Holiday is my favorite lesbian mystery series to recommend. It hits all the marks of a great mystery, well-developed characters and then also humour and banter along the way.

I would say TW for drug abuse, parental abuse, teen death and the spoiler of she doesn't get the girl.

[Mx Phoebe · Rating 4 out of 5]

The mystery is good if not a little obvious.

I love Sister Holiday so I’m a fan of whatever she does.

“Thank you, Gillian Flynn Books, for providing this book for review consideration via NetGalley. All opinions are my own.”

[Kendall]

Some of the best Acknowledgments I've ever read. Everybody, you've just GOT to read these Acknowledgments.

[J R · Rating 5 out of 5]

fun and effective detective story. I loved the previous books in the series and this one was perfectly solid, as well. 5 stars. tysm for the arc.

[Hugh Minor · Rating 4 out of 5]

This series keeps getting better & better. I could not put this one down and when I finished, I wanted more. So when is the next one?

[Carolyn · Rating 5 out of 5]

This one is fun

[Grace Koshida · Rating 5 out of 5]

New Orleans school year is ending and Sister Holiday is preparing for her permanent vow ceremony. But when a popular student dies from a fentaynl overdose, Sister Holiday and her PI partner Riveaux are shattered but determined to find justice. As more students become victim to this toxic drug, Sister Holiday agrees to go undercover to find the drug dealers and finds herself testing the personal and professional limits.

[Angela Harding · Rating 5 out of 5]

Three Words : Queer Smoking Nun.
Three More words: Sleuthing, New Orleans.
This Book and its predecessors will bring you into several types of worlds collie in one. No matter your background, no matter your gender, no matter your job, no matter your race - YOU MATTER and your opinion matters - Combine that theme with a murder / group of murders attacking both a secular and religious community? BUY THE BOOK - READ THE BOOK - LOVE THE BOOK!