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The Society of Unknowable Objects

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What to expect

Brought to you by Penguin.

Get ready to be spellbound by the new, fantastical novel from the Sunday Times bestselling author of fantasy sensation The Book of Doors . . .


The world of unknowable objects - magical items that most people have no idea possess powers - has been quiet for decades . . .

But three current members of a secret society have remained watchful, meeting every six months in the basement of a bookshop in London. They are pledged to protect their archive of magical items hidden away, safe from the outside world - and keep the world safe from them. But when Frank Simpson, the longest-standing member of the Society of Unknowable Objects, hears of a new artefact coming to light in Hong Kong, he sends the Society's newest member, author Magda Sparks, to investigate.

Within hours of arriving in Hong Kong, Magda is facing death and danger, confronted by a professional killer who seems to know all about unknowable objects, specifically one that was stolen from him a decade before. Magda is forced to flee, using an artefact that not even the rest of the Society knows about.

Returning to London, Magda learns hers is not the only secret being kept from the other two members. And that the most pernicious secret is about the nature of the Society’s mission. Her discoveries will lead her on a perilous journey, across the Atlantic to the deep south of the United States - not in pursuit of an unknowable object, but an unknowable person: the killer she first faced in Hong Kong. In doing so, Magda begins to understand that there are even more in the world who are chasing these magical items, and that her own family’s legacy is tied up in keeping all these secrets under wraps.

Magic has always been too powerful to reveal to the world. But Magda will learn there might be something even more powerful: the truth.

'A dazzling, globe-trotting thriller with a spectacular dash of magic. Like Michael Crichton at his finest, but with fantasy. Brilliant stuff!' SUNYI DEAN, bestselling author of The Book Eaters

© Gareth Brown 2025 (P) Penguin Audio 2025

Critics Review

The Society of Unknowable Objects is a dazzling, globe-trotting thriller with a spectacular dash of magic. Like Michael Crichton at his finest, but with fantasy. Brilliant stuff!
SUNYI DEAN, author of The Book Eaters
Huge fun; a fast-paced globetrotting tale.
SFX Magazine
Endlessly inventive, Brown transports the reader to new worlds filled with adventure and magic.
A. J. WEST, author of The Betrayal of Thomas True
The Society of Unknowable Objects utterly demolishes the difficult second book syndrome. A thrilling, globe-spanning adventure that wrong footed me at every turn, and like The Book of Doors, features a truly memorable villain.
ADAM SIMCOX, author of The Dying Squad
Filmic, fast paced and brilliantly imaginative, Gareth Brown’s The Society of Unknowable Objects is a thrilling read that will leave you eager for the next instalment of this hugely entertaining fantasy series.
ANITA FRANK, author of The Good Liars
Fantastical . . . so begins this quirky adventure with echoes of 'Raiders of the Lost Ark' and The Da Vinci Code.
DAILY MAIL
A fast-paced flight of magic, mystery and whimsy, whisking readers on an around-the-world adventure alongside a lovable cast of characters tasked with protecting the world’s most valuable secret — and perhaps keeping a few secrets of their own.
NIKKI ERLICK, author of The Measure
The Da Vinci Code meets magic in a rollicking tale of secrets and espionage. I loved the international settings, the diverse cast of characters, the edge-of-your-seat plot . . . a pacy, action-packed joy of a read!
FIZA SAEED McLYNN, author of The Midnight Carousel
Gripping, fantastical story . . . whisking readers from a cosy bookshop in London to the bustling cityscape of Hong Kong to a forgotten town in the deep south of America. It’s full of impossible magic, damning secrets and ordinary characters wrestling with extraordinary objects. But the best element of this story is its dark, cinematic heart, which explores what happens when god-like power is placed in the wrong hands . . . Brown weaves an intriguing mystery.
CULTUREFLY
Brown’s propulsive plot and plucky heroine keep the pages turning. It’s good fun.
PUBLISHERS WEEKLY
Author Gareth Brown
Narrator Olivia Vinall
Duration 11 hours and 27 minutes
Release Date
ISBN 9781529947090
Format Audiobook
Publisher Transworld
Genre Contemporary fantasy, Crime and mystery fiction, Thriller / suspense fiction, Urban fantasy
Availability AU, GB, IE

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