By this date in 1958, Agatha Christie had been publishing her mystery novels for nearly 40 years.
With roughly three–quarters of her books in print by that time, it is fair to say that "Ordeal by Innocence," which was published on this day in 1958 (when Christie was 68), was a product of her later period as a writer, and it was generally well received by critics. I've always felt it was one of the best of her later works.
It was kind of unusual, really, in the sense that it did not feature either of her most popular detectives, Hercule Poirot and Miss Marple. And it really didn't use some unique plot device. In fact, it was rather conventional.
I guess the most noteworthy aspect of the story was its use of amnesia as a plot device. That is something that had been used before by others, but it was noteworthy because of something that happened in Christie's personal life.
More than 30 years earlier, Christie disappeared for about a week and a half and insisted she couldn't remember anything about the unaccounted–for time. Perhaps "Ordeal By Innocence" was her way of coming to terms with that mostly unexplained period in her life.
That is purely speculation, of course, but Christie did list "Ordeal By Innocence" as one of her personal favorites — and never said why.
The role that amnesia played in the story was secondary, I suppose. It was not the murderer but the detective who suffered from amnesia — and the detective wasn't really a detective, for that matter. He was a physician who lost his memory on the night of the murder. Had it not been for that, he could have been the alibi for the person who was convicted of the murder during the doctor's — shall we say? — absence. It was while he was recovering from his amnesia that the doctor learned what had happened and tried to set things straight.
The doctor was typical, I guess, of the non–detective detectives Christie used in books that didn't feature her actual detectives. Although he had no training in law enforcement, circumstances forced him to assume that role, and he discovered he had a certain aptitude for it.
Ultimately, the thing I always liked about "Ordeal By Innocence" was the fact that, in the end, the question of whether justice would be done was left up in the air. It was a reminder that justice is neither entirely blind nor entirely fair.
