Thought it might help if I could visualize what the heck the Fens are, so I went looking....OH. Marshes, basically. (Oh, and this country is where Graham Swift's Waterland is set -- I saw the movie and read the book, so I have a better mental picture now.)
First reaction: "It's kinda like British Holland!" No?
This isn't.....a pastoral, exactly, but it seems like the solar opposite of Murder Must Advertise, which I haven't read (yet) (maybe) but has the City setting, bright repartee, disguised identities, and so on -- that's a harlequinade. What would this be? It's a City gent in the country, but it's not like the Phaedrus or Midsummer Night's Dream. Rather sober, somber and sad. Water, stone, marsh, liminality, music, iron, reverberations, darkness. A nocturne.