The crooked hinge.

It seemed kind of long and was a complicated story.
But it was always interesting.
Sometime creepy always clever.

It would help if I was a middle to upper class British citizen living in London in the 1920s to 1930s.
There are a lot of references to plays and books and society that I either had to look up or just skip over.

I don't normally read mysteries but I'm glad I read this one.