Unexpected Night by Elizabeth Daly

Amberly Cowden had been seriously ill his whole life. If he survived to his 21st birthday, he stood to inherit one million dollars. If he died before then, the money was to go to distant relatives in France. It was late at night now, a few hours short of his birthday, and he was in a car with his sister Alma, his aunt Eleanor, and his tutor,  Hugh Sanderson. They were on their way to attend a theater performance by Amberly's cousin Arthur Atwood at a small summer theater. Amberly, who had been able to do so little in life due to his heart condition, very much admired his flamboyant cousin and had offered him financial aid for this theatre.

On their way to the hotel where they would be staying, the Cowden party stopped to visit  the Barclays. Mrs. Barclay was Amberly's aunt, and she was married to Colonel Barclay. They had one son Frederick who was also in the army. Also visiting with the Barclay's that night was a young man named Henry Gamage who was an expert in manuscripts. The Cowdens arrived, and stayed for a short visit, and departed for their hotel, Ocean House where they would arrive after one a.m. Amberly was now 21 and a millionaire, and he proudly signed the hotel register for the people in his party.

The next morning, Amberly's body was discovered at the foot of a cliff. He had apparently left the hotel shortly after arriving and had walked to the cliff possibly to meet somebody. The police were notified and Inspector Mitchell arrived to investigate. It was assumed that Amberly had become ill while he was at the cliff, had lost his balance, and fell over the edge.

Henry Gamage had an inquiring mind and was drawn into the investigation. It was said that Amberly had drawn up a will which left $100,000 to his cousin Arthur, $100,000 to his cousin Fred, $100,000 to Eleanor Cowden, and the rest to his sister Alma. This will could not be found, so it was assumed that the one million dollars would go to his sister Alma who was only 19 and would not receive the inheritance until she was 21. She said that she would honor these bequests. She was so distraught over the death, and the events which followed it, that she retired to her room.

Gamage went to the summer theater to meet Arthur Amberly and found that a death had also occurred there. An actress had died from what appeared to be an overdose of morphine. Before Gamage arrived at a solution to the causes of these deaths, several attempts would be made on the life of a one person involved, and another death would occur.

The initial situation in this book is remarkably improbable. However, it does set the stage for a rather clever ending. This was Henry Gamage's first appearance in a mystery novel and fifteen more books would appear in this series. The book was published in 1940, and is still in print.