Miss Marple on Mystery!
A week ago, I watched Mystery! on PBS. They were showing a new Miss Marple episode, starring Geraldine McEwan, entitled Nemesis. For the official write-up of that episode, go here. While you're over there, you might also read the interview with McEwan for her ideas about Miss Marple.
Now I had read the book some years back so I had a vague recollection of how it went but as I watched the episode, I puzzled more and more over the presence of the two Benedictine nuns in the story [see link above]. I was fairly sure that Agatha Christie never had nuns as characters in any of the stories featuring Miss Marple. So falling asleep before the episode was over, I made a note to myself to revisit the mystery, Nemesis, and check whether I was right. Turned out that I was! There were "sisters" in the story, but in the sense of blood relations rather than members of a religious order. It seemed a rather odd change; surely more modern viewers can identify immediately with the concept of a blood relation than with professed religious. I wasn't alone in the question. There were a number of viewers over at the PBS Mystery! forums wondering at the departure of the current set of episodes from the actual Christie plots. The response from the production company is captured here.
On the one hand, I suspect that Christie's expressed sense of morality is fairly foreign to modern sensibilities. Viewers, had the script adhered to the text more closely, might have wondered what the fuss was all about; so a young girl falls in love and secretly plans to marry a bad young man. As justification for murder, it seems a bit thin. However, if you recast the young woman as a novice in a religious order, then it's seems more intelligible that another member of that order might be moved to murder on the grounds that Verity (the novice) has violated her promise as a Bride of Christ. We believe that religious fundamentalism can cause murder. Overly controlling relatives just seem anti-climactic.
On the other hand, I don't care for the practice of "updating" a text in order to present it to new audiences. It is another instance of copyright holders and literary executors working to preserve the brand of an author name (for financial reasons) without much regard for the integrity of the work itself.
Personally, I'd come back to haunt any literary executor who did that to my work...