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THE DUMAT SOCIETY: A Mystery Thriller
From the author of The Ancient Code comes a new thriller for fans of Dan Brown, Michael Crichton, and mystery adventures.
A stand-alone novel that also serves as a sequel to the Ex Libris series.
Sarah is enjoying a sabbatical from her studies and has found herself in St. Louis, where—for once—life feels good. She’s in love with Derry, a bright and charming math student, surrounded by friends, and her biggest worry is whether she wants to return to her old life as a student.
But her peace is short-lived.
After a horrific murder, Sarah becomes the target of a relentless killer. Her investigation pulls her into the depths of a decades-old mystery involving the disappearance of a group of brilliant mathematicians—once poised to revolutionize their field.
They called themselves The Dumat Society.
A stand-alone novel that also serves as a sequel to the Ex Libris series.
Sarah is enjoying a sabbatical from her studies and has found herself in St. Louis, where—for once—life feels good. She’s in love with Derry, a bright and charming math student, surrounded by friends, and her biggest worry is whether she wants to return to her old life as a student.
But her peace is short-lived.
After a horrific murder, Sarah becomes the target of a relentless killer. Her investigation pulls her into the depths of a decades-old mystery involving the disappearance of a group of brilliant mathematicians—once poised to revolutionize their field.
They called themselves The Dumat Society.
348 pages, Kindle Edition
Published July 15, 2025
113 people are currently reading
18 people want to read
About the author
T.S. Falk
24 books87 followersT.S. Falk is a lifelong adventure enthusiast and when a certain pandemic hit, he started writing the books he would like to read.
THE AUTHOR HAS NO SOCIAL MEDIA PROFILES AND ALL PROFILES OUT THERE ARE FAKE AND NOT CONNECTED TO THE AUTHOR AT ALL!
If you want to reach him, you find an e-mail address to do so at the end of each book!
THE AUTHOR HAS NO SOCIAL MEDIA PROFILES AND ALL PROFILES OUT THERE ARE FAKE AND NOT CONNECTED TO THE AUTHOR AT ALL!
If you want to reach him, you find an e-mail address to do so at the end of each book!
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Displaying 1 - 16 of 16 reviews
July 19, 2025
T.S. Falk has jumped to the top of my list of favorite thriller authors. Like the other greats, Rollins, Chrichton, Berry, and Lincoln and Child, he presents a likely subject and proceeds to weave a woolly tale around it.
The Dumat Society covers two generations of students working on a mathematical theorem leaving a bloody trail of bodies in its wake. Yes, I did say a math theorem leaving bloody bodies. One of the reasons I have come to love Falk's writing is his unique subjects.
Tracking the Dumat Society falls into Sandra Wilderman's lap when she is bumming around the U.S. and falls in with a young man named Roderick Jones, whom she calls Derry. Three other students and Derry are challenged by their Professor to complete a mysterious old math theorem.
By the end of the book, you will seriously question who is running our government, any government, and whether the people you thought you knew your whole life are who they say they are. I was left with the feeling that our Society is on the brink of disaster for more reasons than we can possibly imagine.
The Dumat Society is a wonderful standalone book. I do recommend for a richer experience, that you start by reading the first book in The Ancients series. Anything T.S. Falk writes is worth reading.
The Dumat Society covers two generations of students working on a mathematical theorem leaving a bloody trail of bodies in its wake. Yes, I did say a math theorem leaving bloody bodies. One of the reasons I have come to love Falk's writing is his unique subjects.
Tracking the Dumat Society falls into Sandra Wilderman's lap when she is bumming around the U.S. and falls in with a young man named Roderick Jones, whom she calls Derry. Three other students and Derry are challenged by their Professor to complete a mysterious old math theorem.
By the end of the book, you will seriously question who is running our government, any government, and whether the people you thought you knew your whole life are who they say they are. I was left with the feeling that our Society is on the brink of disaster for more reasons than we can possibly imagine.
The Dumat Society is a wonderful standalone book. I do recommend for a richer experience, that you start by reading the first book in The Ancients series. Anything T.S. Falk writes is worth reading.
September 5, 2025
Meet miss Sarah Superwoman, she fights men in top shape, shoots well even with her left hand. She's smart, she's hot, she talks smack, she's so badass. She's also an annoying a Mary Sue who is gifted with everything except humility.
The story was... far fetched to put it nicely. But it was catchy nonetheless. The biggest annoyance is the main character. By the end I was starting to root for the bad guys because I found her so annoying. In many ways, she's the carbon copy of Ashra from Falk's other book series which I got tired of too. Even their names are anagrams!
So if you love Ashra, you'll love Sarah. However if like me you've grown tired of Mary Sue characters, then this book might not be for you.
The story was... far fetched to put it nicely. But it was catchy nonetheless. The biggest annoyance is the main character. By the end I was starting to root for the bad guys because I found her so annoying. In many ways, she's the carbon copy of Ashra from Falk's other book series which I got tired of too. Even their names are anagrams!
So if you love Ashra, you'll love Sarah. However if like me you've grown tired of Mary Sue characters, then this book might not be for you.
October 14, 2025
A top thriller - I have read most of the T S Falk 'historical' thrillers ' This one matches very well against the others . I had my doubts to start with - but they vanished once the plot got moving .
The plot is not new - in that many novels have been written regarding searches for ancient documents / artifacts that will have a good /diabolical effect on the world if they are exposed to the world / churches / etc. However , T S Falk maintains the mystery to a nail biting level - in spite of a lot of killings etc, which does take a bit of a shine off the story in the latter end of the book .
A good read .
Helen Edwards.
July 25, 2025
Better mystery than Robert Conan Doyle
All of these books are great mystery reads. I liked that the protagonist was female nice departure from traditional mysteries. I also liked that it occurred
in many different countries. A little disappointed, however, that Sarah didn't wind up with the former priest, Dr. Bauer. Recommend for any mystery gloves and those who like unrequited romance.
All of these books are great mystery reads. I liked that the protagonist was female nice departure from traditional mysteries. I also liked that it occurred
in many different countries. A little disappointed, however, that Sarah didn't wind up with the former priest, Dr. Bauer. Recommend for any mystery gloves and those who like unrequited romance.
July 20, 2025
who knew a mathematical formula could make such an entertaining story
A excellent addition to the series. Once again Sarah has found trouble, this time in regards to a mathematical formula. Falk is an artist who tells a tale unlike others. I really hope we see more of Ms. Wilderman!
A excellent addition to the series. Once again Sarah has found trouble, this time in regards to a mathematical formula. Falk is an artist who tells a tale unlike others. I really hope we see more of Ms. Wilderman!
August 7, 2025
Sarah has a talent for finding trouble.
A summer fling with a brilliant math student turns into something far more sinister and completely unexpected. Yep, it’s a math thriller and a great one. Loved every minute.
A summer fling with a brilliant math student turns into something far more sinister and completely unexpected. Yep, it’s a math thriller and a great one. Loved every minute.
September 1, 2025
Another Great Read in the Series
The Dumat Society delivers much as the previous adventures of Sarah and Patrick have. Easy fast reading because there is a story to be told and read. Great characters, from the stars to the supporting ones. Fun reading!
The Dumat Society delivers much as the previous adventures of Sarah and Patrick have. Easy fast reading because there is a story to be told and read. Great characters, from the stars to the supporting ones. Fun reading!
October 15, 2025
The Dumat Society
This was quite an adventure. It features a bunch of people trying to solve an impossible mathematical equation and getting killed for their efforts. It’s enough to make you swear off math. But a great story.
This was quite an adventure. It features a bunch of people trying to solve an impossible mathematical equation and getting killed for their efforts. It’s enough to make you swear off math. But a great story.
July 20, 2025
great read
Another excellent book by Falk. Have yet to ever be disappointed with his work.
Once you try one, your hooked
Another excellent book by Falk. Have yet to ever be disappointed with his work.
Once you try one, your hooked
July 25, 2025
Good stuff
This series is his best so far. I enjoyed his other books but these are on another level. Thoroughly enjoyed all 3 of them so far, I hope we get more.
This series is his best so far. I enjoyed his other books but these are on another level. Thoroughly enjoyed all 3 of them so far, I hope we get more.
July 27, 2025
Excellent
This book is very interesting. I couldn't stop reading until I finished it. If you like mystery and adventure, this is for you.
This book is very interesting. I couldn't stop reading until I finished it. If you like mystery and adventure, this is for you.
September 25, 2025
Just finished the third and final book in series and Fantastic again. Completed the Ancients collection...another Fantastic.
October 26, 2025
Five Stars
This is the fifth T. S. Falk I have read and I loved each one. He writes so well. His characters are so alive it's like watching an exciting action movie.
This is the fifth T. S. Falk I have read and I loved each one. He writes so well. His characters are so alive it's like watching an exciting action movie.
December 11, 2025
Great Read
Twisting adventure and a joy to read. You won’t be able to put it down as it grips you. Enjoy the ride.
Twisting adventure and a joy to read. You won’t be able to put it down as it grips you. Enjoy the ride.
January 5, 2026
Dumas society review
Great read, gripping story plot and endless action and adventure. Cast was well developed and the constant link to other characters was brilliant?
Great read, gripping story plot and endless action and adventure. Cast was well developed and the constant link to other characters was brilliant?
August 19, 2025
my thoughts
I loved the story line and enjoyed following Sarah Wilderman again. I have read all the books that have her as the central character. The idea that mathematics an explain God and the creation of the Earth is is leaving out the sacred account found in the Scriptures. Thank you Mr Falk for your books. I have enjoyed all of them that I have read.
I loved the story line and enjoyed following Sarah Wilderman again. I have read all the books that have her as the central character. The idea that mathematics an explain God and the creation of the Earth is is leaving out the sacred account found in the Scriptures. Thank you Mr Falk for your books. I have enjoyed all of them that I have read.
Displaying 1 - 16 of 16 reviews