Hitchcock Wanted To Cast Cary Grant and Eva Marie Saint
Evidently seeking to duplicate the success of "North by Northwest," Hitchcock sought Cary Grant and Eva Marie Saint for the roles played by Newman and Andrews in the film. Grant said "no," and Universal indeed wanted Hitchcock to use really big stars for both the male and female leads, and Andrews was "hotter" than Saint thanks to "Mary Poppins" and "The Sound of Music."
Personally, I'm glad that Grant and Saint didn't do this film, for though it is not bad, it is not as good as "North by Northwest."
Paul Newman and Julie Andrews were an interesting pair for the roles -- and the last big stars to ever agree to work in a Hitchcock picture.