The Notebooks of Tennessee Williams, as compiled, databased, and published by Margaret Bradham Thornton, are one of the most astonishing acts of scholarship I have seen (and I have seen plenty).
One example: Here's a painting called Poker Night, by Thomas Hart Benton, based on what we know of as A Streetcar Named Desire, given as a present by David Selznick to his estranged wife Irene.
Just a footnote in this book.
Kit Stolz 