One of the reasons
Alfred Hitchcock shot the movie in black and white was he thought it would be too gory in color. But the main reason was that he wanted to make the film as inexpensively as possible (under $1 million). He also wondered if so many bad, inexpensively made, b/w "B" movies did so well at the box office, what would happen if a really good, inexpensively made, b/w movie was made.
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