Take Two Hen Lobsters
Book four of EF Benson's series of Mapp and Lucia novels is the one which finally brings them together. It's easy to look at the previous books from here and think that this was always Fred's intention but my suspicion is that the idea of bringing them together only came to him after he's written the two previous Lucia books and 'Miss Mapp'.
Whatever, the joining of these two characters provides the spice that was missing from the previous books in that they both, finally, have an adversary worthy of each other.
It is a gorgeous book. A real period piece about life among the independently wealthy middle classes between the wars and it's full of little episodes all of which come together to a magnificent conclusion.