Decahedron
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Pub Date Sep 15 2026 | Archive Date Dec 15 2026
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Description
Humanity’s Judgment Begins Now
In 2175, humanity has conquered scarcity, colonized the solar system, and mastered technologies once thought impossible. Then, something unexpected emerges from the edges of space.
The object is enormous, ten-sided, and older than anything humanity can comprehend. Dubbed the Decahedron, it takes position near Saturn and humankind does what it has always done when confronted by the unknown: studies it, speaks to it, and prepares to fight it. But every attempt to understand the object brings consequences, and every response only intensifies the threat.
On Earth, a widowed Princeton University linguist named Julian Wexler receives a visitor. Calling himself Virgil, the mysterious stranger knows what the Decahedron is and what has happened to those who have encountered it before. Virgil believes Julian may be humanity’s best hope of surviving what comes next.
Because the Decahedron has not come to invade. It has come to judge.
For fans of Cixin Liu’s The Three-Body Problem, Decahedron is a thoughtful, speculative debut centered on first contact with an enigmatic ancient intelligence and the question of whether aggression or humility will determine humanity’s survival.
Available Editions
| EDITION | Paperback |
| ISBN | 9798996941520 |
| PRICE | $17.99 (USD) |
| PAGES | 282 |
Links
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Buy on Amazon Buy on BN.com Buy on Bookshop.orgAverage rating from 10 members
Featured Reviews
Neville T, Reviewer
A good first contact story mostly executed well. The pace was good I did not get bored as sometimes these type of sc- fi can. A few of the characters were stereotypes, the main character was good. Overalk this is a good debut. Thanks to Empyrean Gates Press and Netgalley for this review copy
Anthony P, Reviewer
Very unusual moral to this science fiction story. It's well worth the read and you will be engaged until literally the last page. I have always wondered how first contact would be, and this is probably a outcome we should consider.
It was more intense than I expected. My nerves were all over the place. If I had been the protagonist, I would've died during the first under-pressure situation.
I loved how the author reinforced the sense of urgency by adding a countdown in the middle of the characters' actions or thoughts. My nerves didn't appreciate it. As an emotional reader, I got all tense. But at the end of the day, that's what I want from a good story. To make me feel and/or think.
This book is mostly plot-driven, and even though I was hooked right away, as soon as I read "dark forest theory" and "ten dimensions," I knew things were going to get even better.
We have our heroes, trying to figure out how to save not Earth, but the entire solar system, so you know, zero pressure, jajaja. As much as I liked them and how they come together, I hated the villain more. AKA Deckland.
That man was utterly unhinged, drunk on power, and totally delusional. He actually compares himself to gods. The worst part is that he is in a position of power where he can do real damage. I found him absolutely terrifying.
My favorite part is the friendship between Julian (one of the MCs) and Virgil, an AI created by a long-gone civilization, a victim of the Decahedron.
This book is about connection, sacrifice, but also about the need for new approaches to break the cycle. It also makes you think about the role ethics play (or should play) in technology and weapon development, and how dangerous they can be in the wrong hands.
My only complaint is that I would've loved for Sirena to have a more significant role from the beginning. She is intelligent, determined, and kind.
There were a few minor timing inconsistencies in one or two scenes, and also, some space stuff didn't feel accurate enough. But I understand that a fight in 0 gravity would be quite boring without additional effects. None of this has a major impact on the plot, but if you are a detail-oriented reader, it might bug you a bit.
I enjoyed the action, the tension, the spaceship fight scenes, and the ending. I love these kinds of endings! If you want to find out, I invite you to read this book. For me, it's a yes.
Bruce E, Reviewer
Decahedron by Dan Sodano is a killer piece of speculative sci-fi. It nails that same creeping, existential dread you get from The Three-Body Problem or Ted Chiang’s Arrival, but keeps things fast-moving and accessible.
The story takes place in 2175, after humanity has wiped out poverty, expanded across the solar system, and convinced itself it has all the answers. That confidence completely shatters when a giant, ten-sided object suddenly parks near Saturn. It’s older than anything in the known universe and completely ignores every signal we send. As fear spreads back on Earth, our desperate attempts to force contact only make everything worse.
What makes it work so well is how genuinely alien the threat feels. It isn't a ship full of classic movie monsters; it’s an unreadable mathematical presence that instantly puts human ego in its place. Seeing a hyper-advanced society fall apart simply because it can't measure or control something is fantastic.
The middle section gets a bit heavy on scientific debate, and the characters are more about big ideas than big emotions. Still, if you love sci-fi that makes you stare at the ceiling and contemplate our tiny place in the universe, it’s an easy 4 out of 5 stars.
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