21 - A Proscenium Box. The Window at the White Cat by Mary Roberts Rinehart.

21 - A Proscenium Box. The Window at the White Cat by Mary Roberts Rinehart.  The Window at the White Cat is a 1910 mystery novel by Mary Roberts Rinehart, featuring lawyer Jack Knox, who investigates the disappearance of a state treasurer, Allan Fleming, after his daughter seeks his help. The case becomes more complex with the disappearance of the aunt and the involvement of a seedy political club called "The White Cat," leading to murder and political intrigue. It's a classic "Had-I-But-Known" mystery, known for its Gothic heroine and focus on a seemingly ordinary woman caught in extraordinary circumstances.