Unexpected Night, by Elizabeth Daly (epub/Kindle)

New York handwriting and rare book expert—and a gentleman sleuth—Henry Gamadge is vacationing in coastal Maine when the police there need his help. It’s a strange case involving a seemingly natural death, a large inheritance, a mysterious nighttime rendezvous, and a troupe of summer stock actors who start dying off. Something is clearly afoot, but nothing quite seems to fit. With an eye for frauds, Gamadge is just what the local detective needs to throw the book at a killer...