I also recommend John Dickson Carr - 'The Judas Window' and 'The Three Coffins' in particular. The last is in my opinion one of the best locked room mysteries, and there's a particular monologue in it that you can say serves as a primer to how to puzzle out the Locked Room subgenre.
As for Columbo - 'Death Lends a Hand' - it does a few things different from the usual formula, and the interplay between Columbo and Brimmer is quite well-done.
no subject
As for Columbo - 'Death Lends a Hand' - it does a few things different from the usual formula, and the interplay between Columbo and Brimmer is quite well-done.