A favourite sub-category of the crime genre of which I am particularly fond. There are several we all know such as Conan Doyle’s Sherlock Holmes story “The Speckled Band” to which the resolution is quite surprisingly simplistic at the same time and there are countless ones in David Renwick’s Jonathan Creek series, with Ghosts Forge (and the locked room aspect a small subplot) and Danse Macabre (disappearing kidnapper and murderer) being particularly impressive ones.
One which does stand in my mind is a 1930s Sexton Blake story called “Suspended from Duty” in which Sexton Blake’s police contact Inspector Coutts runs foul of a conspiracy and well, look at the title. Part of the story involves a man being shot in a locked room and a series of absent characters, Sexton Blake is surprisingly absent for the bulk of the story and only really turns up at the end. The solution is rather bizarre and I am not convinced it is scientifically possible but it renders the mystery to a freak accident, nevertheless it is a memorable solution to the incident.
Myself, well I have outlined one or two, though one is a sort of inversion of the situation where I have an abandoned car in the middle of a mountain side where there is no road access and the car is in perfect condition save for a small scratch on the rear windscreen.