I've recently ploughed through several mystery novels by some of the best known writers, Golden Age and modern, examining the evolution of the gentleman detective.
I started by reading two of Georgette Heyer's books, featuring her detectives Inspectors Hemingway and Hannasyde. I started with Heyer because I enjoyed her mystery The Unfinished Clue, which I reviewed previously on my blog.
Death in the Stocks and No Wind of Blame were both enjoyable, but did not rise above casual consumption reading. Heyer writes characters very well, but the plots are tiresome. As in The Unfinished Clue, there is a stock cast, including a solid, no-nonsense young woman who finds most of the clues and, unexpectedly, love. Both of these novels contain a good bit of farce, which detracts from the solving as it grows into a bigger part of the novel. The plots are pedestrian and the actual murders poorly worked out. It is said that Heyer's husband worked on the plots for her. He was an engineer turned barrister, and engineers and barristers are the male leads.
The detectives, Hemingway and Hannasyde, only appear in the last third of the novels. They are poorly developed and forgettable personalities.
Looking for more substantial fare, I read the first two of Dorothy L. Sayers' novels starring Lord Peter Wimsey. These are a blast, and I thought the first one was really excellent.
Sayers cuts to the chase in modern fashion in the first book, Whose Body? The detective is on the scene almost from the first page. He is a strong, witty, and well drawn character. The second son of a duke, Wimsey is young, rich, and fascinated with old books and detection. His valet, Bunter, is a wonderful foil. Written in the middle 20's, the effects of the World War are still vividly present in this novel.
The second Wimsey, Clouds of Witnesses, is less successful. The plot revolves on too many coincidences. Wimsey is shot in the shoulder and suffers a broken collarbone, which goes unspoken for the rest of the novel. Still, fun to read. I look forward to following the path of Wimsey.
Having tried Wimsey, I went on to sample Ngaio Marsh's Roderick Alleyn. While Alleyn is also the second son of a noble (an earl, now), he is a Scotland Yard working stiff (Detective Inspector) as well. In his first outing, he solves a standard English country home weekend party murder. He also meets his regular foil, Nigel Bathgate, a young journalist. I found Alleyn less engaging than Wimsey, but will give him a second chance.
Jumping forward, the modern author Elizabeth George has also created a noble detective. He is Thomas Lynley, the Eighth Earl of Asherton. No second son, he is the Earl himself. I think there is a certain title inflation going on here. Lynley is also a Scotland yard DI, paired in most of the books with Detective Sargent Barbara Havers. Havers is of lower class origins, and her awareness of class differences with Lynley crops up regularly.
George's books are both mysteries and soap operas. Through the first four, there is as much emphasis on the personal life of the detective and his friends as there is on the case. This is just a tad wearisome, but I admit I am a sucker for this kind of thing. Each Lynley book has one main and several side murders. Written in the '80's, it is funny to watch the author grapple with rapidly changing technology. Computers are often referred to as 'word processors', as if this were a distinct appliance, for example.
The fourth Lynley book attempts to fill in some of his backstory, at the cost of some tortuous continuity issues. Too much of the book is taken up by the soap opera aspect of the storytelling.
As much as I am enjoying George, Lord Peter Wimsey is by far my favorite character. While he is decidedly eccentric, he is also the most human of these detectives, and the best drawn. I suppose this is saying that Sayers is the best author, as well.
The classic SF detectives are Elijah Bailey and R Daneel Olivaaw. I think the stories by Isaac Asimov featuring this pair, a New York detective and his robot sidekick, are my baseline for all other detectives, even Holmes and Watson. This is just my personal history at work, since I read Asimov earlier than any other detective fiction.