The After House by Mary Roberts Rinehart

American writer of mystery novels known for their humor and ingenuity. The novel begins: By the bequest of an elder brother, I was left enough money to see me through a small college in Ohio, and to secure me four years in a medical school in the East. Why I chose medicine I hardly know. Possibly the career of a surgeon attracted the adventurous element in me. Perhaps, coming of a family of doctors, I merely followed the line of least resistance. It may be, indirectly but inevitably, that I might be on the yacht Ella on that terrible night of August 12, more than a year ago.