It's one of the five largest mystery bookstores in North America that specializes in historical mysteries and houses more than 10,000 titles.. In Short Open and spacious, the store has wall-to-wall shelves with books by Agatha Christie and other popular authors of mystery books. If customers don't find what they want, the staff takes orders. Book signings by famous mystery authors take place every month, and fresh coffee is always brewing at Author's Cafe. Also, be sure to check out the store's list of upcoming events, list of best sellers and list of recommended books.