I've been wracking my brain, and I just cannot remember the name of any of the books or the author.
There were a couple of books featuring the same person, set in the 1930s or 40s I think (but I could be wrong). She isn't a very likeable person, and is described as rather plain looking.
One was a murder story set in a boarding school.
Not much to go on, I know! Does anyone recognise the book(s)?
I read them when I was in my 20s, so over 30 years ago now.