The title "Busman's Honeymoon" is sort of a play on words. Look up busman's holiday in the dictionary. In fact it was a play that was also made into a movie "Haunted Honeymoon" (1940) starring Robert Montgomery and Constance Cummings. There are still some short stories and a novel finished by someone else; however Busman's Honeymoon is the last of the novel series containing Harriet Vane. Some of the short stories are "The Haunted Policeman" and "Talboys."
The book starts off with a series of letters from well-known friends of the couple, described previous in Dorothy L. Sayers' novels. They bring you up to date while describing the wedding of Lord Peter Wimsey and Harriet Vane. Some of the charters are just referenced yes it ought on and you will have to have read the previous novels for fuller detail.
The primary thrust of this novel is the relationship between Lord Peter Wimsey and Harriet Vane. With exquisite descriptions of their life and the English environment in which they live. Oh yes, there is also an intriguing mystery for the couple to solve. However the mystery does not overshadow the rest of the story.
One of the most important overlooked items in most descriptions of this book is the expanded explanation of the history and relationship of Bunter to Lord Peter.Strong Poison