Mr. Penumbra's 24-hour Bookstore by Robin Sloan

This 24-hour bookstore in California has members who borrow the same books in the same order. They are part of a society, The Unbroken Spine, that existed for over 500 years.  Members are trying to solve a mystery and when they do, they will be allowed to write their personal story for the society’s library.  Their story is not read until they die. 

Clay Jannon is the narrator and he is one of the workers in the store. When he realized that customers do not regularly visit the store, he begins an on-line ad campaign to attract paying customers. 

One of his tasks as a clerk in the store is to chart down notes on each member when they visit the store.  Mr. Penumbra wants to know what they were wearing, what their mood was, how they smelled, looked, etc.   When Clay discovers the members are borrowing the same books in the same order, he creates a visualization chart to try to find out what the reason is.  There is a mystery underfoot. The alleged mystery is supposed to be the answer to the secret of longevity. 

Clay enlists the help of Kat and another friend to help him solve this mystery.  

Kat works for Google and she acquired one of the coupons for the store. That’s how she met Clay and got involved. Clay goes on a wild adventue to New York to uncover the mystery of the store and the owner, Mr. Penumbra who disappears.

I thought this was a great mystery story involving a bookstore – albeit a kooky bookstore.    Wasn’t fond of the secret society, but I do like the way the author ended the story with a snap shot of what became of the main characters after the mystery was solved.  I would recommend this book.