Decahedron by Dan Sodano —Adult Speculative Science Fiction — September 2026
In 2175, humanity has conquered the solar system and seemingly lives in harmony as it expands outward. That is, until a massive, enigmatic ten-sided object—the Decahedron—enters the solar system.
Julian Wexler, a grieving Princeton linguist, is approached by Virgil, an enigmatic emissary who reveals that the Decahedron is an ancient intelligence that judges civilizations through a single, unspoken riddle.
As humanity’s attempts to understand the Decahedron become increasingly destructive, Julian must decipher its riddle before our instinct to conquer the unknown destroys us all.
Decahedron is a 92,000-word adult speculative science-fiction novel blending first contact, cosmic mystery, philosophical science fiction, and high-stakes action. Readers of Arrival and The Three-Body Problem may particularly enjoy it.
Content warnings/triggers: Violence, death, grief/loss of a spouse, mass-casualty events, existential threat, and nuclear weapons.
Publication date: September 15, 2026
ARC availability: Available now
Review requested by: September 15, 2026, or as close to release as your reading schedule allows.
ARC format: EPUB
I’m looking for honest reviews. There is absolutely no expectation of a positive review.
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