Terror by Twilight by Kathleen Moore Knight, 1942

 

This is Margot Blair #3 (of 4).

Major characters:

• Benjamin K. Embrie, wealthy patriarch
• Sam Embrie, his brother
• Countess Adelaide von Reisenau, his sister
• Count Hans von Reisenau, his brother-in-law
• Brooke K. Embrie, his disinherited son
• Adele Embrie Bourne, his missing daughter
• Arthur Bourne, Adele's husband
• Judith Maine, Arthur's secretary and in line to be wife #2
• Deborah Bourne, daughter of Arthur and Adele
• Adrian Ambrie, Deborah's second cousin
• Remsen Gray, reclusive neighbor
• Dan Murphy, chauffeur
• Donal Craigie, butler
• Janet Craigie, housekeeper, wife of Donal
• Margot Blair, of Norman and Blair, Public Relations
• Corey Graham, newspaper liaison for Norman and Blair, Public Relations

Locale: The Berkshires of western Massachusetts

Synopsis: Millionaire Benjamin K. Embrie hires public relations outfit Norman and Blair, paying a handsome monthly fee just to keep them ready if needed. He then approaches Margot Blair to serve as a support for his sheltered granddaughter, Deborah Bourne, buying her clothes and other things as needed; as her mother Adele Bourne has been missing for years and is presumed dead. Margot gets invited to his home Thistle Hills in the Berkshires to meet Deborah.  Embrie dies while she is en route.

Margot meets Deborah and finds it is believed she suffers from a periodic violent mania, in which it is believed she was responsible for some pet deaths. Embrie's will benefits his family equally, but it turns out that he was on the verge of signing a new will,  leaving everything to Deborah. When his death is found to be by poison, suspicion rests on the family members; who are all trying to point the finger at Deborah instead. 

Margot teams up with her newspaper liaison, Corey Graham and butler Donal Craigie to investigate who killed Embrie, and whether Deborah really has a mania or not.

Review: This has the standard formula of the victim being murdered just prior to signing a new will. (Moral: Don't tell anyone until after you sign it). 

The story is about the relatives "gaslighting" Deborah - making her think she is insane, in order to  get her found incompetent to inherit under a will.

I didn't care for the two instances of killing pets. This dampened my enjoyment of the story. I have read most of K.M. Knight's stories, this is the only one which has that.

I was not able to figure out Adrian Embrie's relationship until the end. He is identified as Deborah's distant cousin, he wanted to marry Deborah, and his parents are named but not connected up to family until at the end it is mentioned he is Sam's grandson (making him a second cousin to Deborah).

Also note the "twilight" in the title does not reference literal twilight, but rather the medical treatment known as "twilight sleep" which is a plot element. An AI inquiry defined this as: "Twilight sleep, also known as Dämmerschlaf, is an amnesic state characterized by insensitivity to pain, which can occur with or without the loss of consciousness. This technique was primarily developed for use during childbirth and involves the administration of a combination of drugs, specifically morphine and scopolamine. The purpose of twilight sleep is to manage pain during labor while allowing the patient to remain in a semi-conscious state."