The Window at the White Cat (Unabridged‪)‬

With all the elements of a timeless mystery, Mary Roberts Rinehart first published The Window at the White Cat in 1910. John Knox is an attorney, not a detective, but Margery turns to him when her father, Allan Fleming, the State Treasurer, does not return home. There are reasons it should not be made known that he is missing. Where is he? 

And then, Aunt Jane disappears overnight, leaving a bloody handprint behind on the staircase wall. Aunt Leticia says pearls are missing, and then she denies it. What does it all mean? 

Rinehart was ahead of her time and has written a very contemporary mystery.