Guillermo del Toro is telling IndieWire that a Black and White cut for "Nightmare Alley" exists, which he "hopes can be seen."

"There is a version of the movie [in black and white] which I hope can be seen. It's not a movie where you turn the color off. The movie is almost like a serigraph in black and white that then has another layer of color. If you saw the movie in black and white, it's not like you just turned the color off. It looks exactly like a movie from the 1940s in a way that is astounding.

I saw “Nightmare Alley” a couple of days ago. It's very digital looking. They didn't seem to even try to put a “film” aesthetic look to it. The aspect ratio was also a little off and should have been 4:3  — del Toro was using very wide lenses for his shots.

Of course, it could still look good in black and white, a lot of the production design matched the 1947 version. There’s also an immaculate use of shadows in this film that could be better suited for black and white.

With all that being said, the film just doesn’t really look and feel like a film noir. It’s rather glossy and modern-looking. That’s why I don’t think this monochrome version is necessary.