I think that Gnomon is the sort of book that critics tend to call a "tour de force" or a "modern masterpiece". This is the sort of novel which writes a great number of cheques with dangling hints and foreshadowing and mysterious themes. It is, I suppose, a puzzle box. But unlike most of the deeply frustrating puzzle boxes I have read and watches, Gnomon pays every one of those threads off with excellent execution and satisfying resolution. It is not being opaque and mysterious just to keep you hanging — this is a thought-out piece which fits together like satisfying sculpture which casts different silhouettes from perpendicular angles of observation. As I'm fond of saying: Harkaway thinks he's being soo clever; frustratingly, he is absolutely right and might even be cleverer than all that.

The premise/trailer. Set in a near-future Britain ruled by a benevolent computer system which sees everything; is governed by continuous, randomized, small-group citizen-democracy; and nudges people towards being their best selves: a principled & well-respected detective is assigned to investigate the death of a suspect in custody. That suspect, a pro-privacy luddite* refusenic of the panoptic destruction of privacy was being "interviewed" using an invasive (but generally safe and benign) brain-scanning/mind reading tool. As our detective plays back the mind-reading recording of the interview, she discovers much more inside the suspect's mind than should be possible, and is (naturally) forced to question the foundations on which her society is built while a mysterious semi-adversary stalks her investigation which is dogged by more coincidences than should be possible.

Gnomon densely interwoven piece of speculative fiction which brushes against but doesn't quite touch the genre markers of sci-fi, but absolutely fires on all cylinders of noir. A complex structure in the text reflects the text's relationship with the reader and interrogates the value and impact of art & literature, and the way we evaluate & disambiguate coincidence and ambiguity in our world mediated through imperfect senses and minds. The small cast of characters are excellently-written, inhabiting their own interconnected worlds with different & distinct flavors, voices and personalities — they'll stick with you long after you've finished the text.

This is a great book which I could read over and over; it's definitely in the running for my desert island choice. I absolutely recommend it to anyone who enjoys Great Literature™, great sci-fi (even if this is only sci-fi-adjacent), well-executed mysteries, hopeful dystopian political fiction (though this is not hopepunk), or gorgeous world-building. Gnomon has a lot to recommend it! Despite its length & density, it is incredibly readable and difficult to put down except for moments where you read an absolutely bizarre paragraph, say "What?" out loud, and then have to sit & think for a minute before continuing.

Please read Gnomon so that I have more people to talk to about it.

• Positive, reverential.