What other admired and / or highly compelling religious themed fiction (or even non-fiction) books you've read so far (with similar or even more interesting themes, characters or setting/s to those in The Nun's Story film, would you like seeing film adapted, because you reckon it's much more compelling and better written than TNS and please explain what the book's story is about and why you admire it.
I read a biography of Aimee Semple MacPherson that I feel that way about, and another of Isadora Duncan by the same author, Daniel Epstein.
He does a huge amount of research into the background that formed these women's characters and activities. He talked to a lot of doctors about how faith healing really works (when it works), for instance (it's not gullibility or hypnosis as you might think). People might think that Isadora was a little cracked, but if you knew the context not.
There is also a book called Fair Clear and Terrible about the Kingdom church/school back in the late 1800s-early 1900s that I wish they would do a film version, but they would probably exaggerate it and make it all Dickensian. There is a website about how The Nun's Story was received by real sisters and one of them said it didn't show enough of the consolation and beauty of religious life. I would worry that a film about the Kingdom wouldn't show enough of why people loved it and wanted to make it work.
I read two other books about nuns based on true stories. One was "The Deliverance of Sister Cecilia about a nun in Communist Czechoslovakia, and another "I Leap Over the Wall", about a nun who left the religious life. I think both stories would make intersting films.