Oh, Peter.
Also, it took me long enough to remember the mystery twist in this one. I remembered the one in Strong Poison on the first page, but I forgot this one.
In part, because this book is less focused on the murder than the previous Peter/Harriet book (a pattern that, of necessity and fortunately, continues).
This is where the murder mystery begins to be a way for the characters to talk about who they are and what they want.
A pattern that reaches its apex in the utterly perfect Gaudy Night.