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Summary

The protagonist, Clay Jannon, is hired by a San Francisco independent bookstore owner -- Mr Penumbra -- to retrieve books from 10 pm to 6 am, at the request of long time bookstore customers holding an unusual interest in highly obscure volumes. When Clay examines one of these books, he sees page after page of unreadable encrypted characters, no spaces, no punctuation. Yet the customers return night after night, returning one book, and taking another. The question is: Why?