Traveling encyclopedia salesman Oliver Quade may be the most unlikely detective to appear in the pages of the pulp magazines of the 1930s. Known for marveling crowds by reciting the memorized contents of The Compendium of Human Knowledge, Quade-known better as The Human Encyclopedia-has a habit of letting this knowledge lead him into the middle of one murder investigation after another. Collected for the first time are the first half of The Human Encyclopedia stories, including the rare early stories: most of which have never before been reprinted. Also including all of the original magazine illustrations and an authoritative introduction by Black Mask conservator Keith Alan Deutsch.