The first piece of serious literature I have read in quite a while, and it came in a heavily annotated edition, comprising the original short story published in an American magazine and the later extended British novel version, as well as examples of the discussions it sparked in the papers at the time it was published, extracts from the protocols of the trials that followed and essays about the book. The story itself was surprisingly interesting and the novel is full of witty aphorisms (which I find myself unable to remember in a quotable quality, however).