For. The. Love.
This is wrong on soooo many levels. It tires me out just to think about it.
I'm not against a reboot or retake on an old Brit mystery series. Sherlock was one of my favorite shows last year. But Sherlock changed one thing: The historical period in which the Holmes stories took place. It was very faithful to the characters, the sidekicks, the baddies, the flaws, the feel, etc. And it modernized intelligently: the use of cell phones, internet, modern psychology "I'm not a psychokiller I'm a highly functioning sociopath."
But in this case...
* Is this going to be modernized? I assume so.
* Is it going to take place in the US? Probably. Americans in Brit roles are rare, and it's being produced by Disney.
* She's obviously going to be younger.
* I doubt the books describe Miss Marple closely (as they do Poirot), but Agatha Christie apparently said she would like to see Joan Hickson play her, as she eventually did, and many consider her the best Marple (as I do.) Certainly the best Marples have been diminutive women. Garner doesn't fit how I'd imagine a young Miss M to look.
But here's the thing. Miss Marple is one of the great Old Women Heroes. The fact that she's OLD and that she's a WOMAN is what makes her character--it's part of how she solves her mysteries. She's been observing human nature for years, and she has all these stories stored up in her mind; she recognizes patterns of behavior, and certain personality types. I'm sure she was a clever and observant young woman, but old age is one of her tools.
She's patient, she listens, she knows how to make people trust her, and talk; and then her brain pieces it all together. She's not a younger woman with ambitions and projects for her own life. She's an observer of other people.
And finally, she's underestimated, often considered a foolish, gossipy old woman. You can't have a Miss Marple without disregard for women, and without disregard for old age.
You can reproduce those things. Maybe they'll make their Miss Marple seem shy. Maybe the men around her will be sexist. I don't know. But the writing is going to have to be damn good to fauxproduce what made that character MISS MARPLE. And they'll still have to make a clever puzzle to boot, so hopefully they'll use an actual Christie plot (and not come up with their own predictable plot à la Gosford Park.)
But even then... even then it will have to be so totally knock-it-out-of-the-park feministly amazing to make this actually ok. Because in the end they're screwing with one of the VERY FEW elderly heroines in the history of movies, TV and literature. Miss Marple as an oldy has been deemed unworthy for the modern day big screen, and that SUCKS.