Reading progress update: I've read 7%.

The Circular Staircase -  Mary Roberts Rinehart

I'm getting distinct vibes of The Ghost and Mrs Muir. I love it.

"The discovery of a small picture fallen from the wall of the drawing-room was quite sufficient to satisfy Liddy that the alarm had been a false one, but I was anything but convinced. Allowing for my nerves and the fact that small noises magnify themselves at night, there was still no possibility that the picture had made the series of sounds I heard. To prove it, however, I dropped it again. It fell with a single muffled crash of its wooden frame, and incidentally ruined itself beyond repair."