I read E.C. Bentley’s Trent’s Last Case (Project Gutenberg’s edition of the novel) in about a day. It’s a short early detective novel from 1913. I can’t recall now where I heard of it, but something about the description struck me as relevant to my detective story interest (that is, in unusual ones). Bentley dedicates the book to G.K. Chesterton in the wake of his The Man Who Was Thursday.
It’s a realist novel, in style probably not that unusual from other works of the time, but the oddity of it (and probably the only part that really interested me) is that the detective (the eponymous Trent) fails to solve the case. Don’t think I am giving away anything here, as it plainly states so on the back of the book–and besides you should know something is wrong when the detective solves his case two-thirds of the way through the novel.
Trent’s ratiocinative powers help him figure out a certain element of the goings-on in the mystery, but ultimately he fails, only finding out the real solution much later through the confessions of others. Trent is portrayed as a bit of a dilettante: painter, newspaper reporter, detective, and, unlike Sherlock Holmes the sine qua non of detectives at the time (still?), a lover.
Bentley gives us an early, fallible detective attached to world, more than just a brain for solving problems (Dupin, anyone?) he is in the world and is thus unable to have all the answers even though he does manage to see one part of the truth, the final revelation is not something he deduces but something that is passed on to him.
It is also worth noting that the first chapter sets up the importance of the victim, a extremely wealther American banker/financier, only, in the end, to tell us that after his death it was realized how little he mattered.
Clerihew, besides being known for this novel, is known for the creation of his own poetic form, the clerihew. It is a quatrain that rhymes aabb. The first line names a person, and they are often humorous. (Wikipedia’s Clerihew page)
(Apparently there is an old movie version with Orson Welles.)