Murder Under A Blue Moon. A Mona Moon Mystery, #1

Mona Moon is not your typical young lady. She is a cartographer by trade, explorer by nature, and adventurer by heart. But there's a problem. Miss Mona is broke. It's during the Depression, and her application has just been turned down to join an expedition to the Amazon. What's she to do? Perhaps get a job as a department store salesgirl. Anything to tide her over until the next assignment. There's a knock on the door.
Who could this be in the middle of the night? Holding a revolver, Mona reluctantly opens her door to a man wearing a Homburg hat and holding a briefcase. "I bring glad tidings. Your Uncle Manfred Moon has died and left you as his heir to the Moon fortune. You are now one of the richest women in the country!" he says. Mona's response is to point her revolver in his face. If the stranger is telling the truth, she will apologize.
If he is a fraud, she will shoot him. That's how Mona does things in 1933.