Mr. Penumbra’s 24-hour bookstore

A book about technology, cryptography, conspiracy, friendship and love

Written by Robin Sloan

Robin Sloan

Robin Sloan is an American best selling author. He debuted with this book, 'Mr. Penumbra's 24-hour bookstore'. He graduated from Athens High School in Troy, Michigan in 1998. He went on to study economics and co-founded a literary magazine called Oats.

When he's not writing he “dorks around in technology” and he has worked at Poynter, Current TV and Twitter, where his job always had something to do with figuring out the future of media.


Illustration by Emily Mahon, taken from the New York Times website

About the book

Mr. Penumbra’s 24-hour bookstore is a book about technology, cryptography, conspiracy, friendship and love. The story starts in a mysterious bookstore in San Francisco where Clay Jannon starts working the graveyard shift. The store has two kinds of customers — random people passing by who wonder how the store stays open, and a dedicated group of people that come in at strange times, never browse and know exactly what they need next. These customers borrow books from high shelves in the dark part of the store, which Clay has been told not to read.


After a while, Clay figures out that this quiet, rarely visited bookstore hides an ancient secret that can only be uncovered by using modern technology. Together with Kat Potente, a Google employee Clay is romantically interested in, he goes on a quest to solve an ancient puzzle. While doing so, he gets help from a friend who got rich by starting a company that specialises in 3D boobs (I kid you not) and a mysterious hacker who never makes an actual appearance.


The book has been released with two covers and one of them glows in the dark, as seen below.



Mr. Penumbra’s 24-hour bookstore

A short review

This book is warm, intelligent and well written. It balances on the intersection of the analog and the digital world, but Sloan's love for books shines through every word. He knows how to make a reader turn pages and adds fun little details to describe how we are getting used to our digital lives (“Kat bought a New York Times but couldn’t figure out how to operate it, so now she’s fiddling with her phone”).

His descriptions of the (digital) lives of the people in the book are so vivid that it is very easy to relate to the book. Although the protagonists seem to find a quick and easy solution for everything — which is the only downside to the story — the book never gets too predictable and Sloan's natural writing style keeps you from putting it down at a comfortable pace.