The Suspicions of Mr Whicher

In 1860, a brutal murder in a fancy country house in the UK produced a scenario that was to serve as a template for many mystery novels in the future. A Mr Whicher, among the first Scotland Yard detectives to act in a Sherlock Holmes-type capacity, is sent to the home of the Kent family to make sense of the case.
What's interesting about the real-life story is not so much its similarities with the classic whodunnits made after it, but the differences: the victim is a young child, the detective universally disliked and ultimately unsuccessful, and external circumstances like culture, politics, and the press play a much bigger part in the proceedings than they ever do in an Agatha Christie novel.
As such, the book is a failure as a mystery novel, but a success as a social history of Victorian England and the place crime took in it. The author is, however, long-winded, taking time to explain such niceties as the etymology of the word 'to detect', and generally repeating herself again and again. It could have been shorter and better.