Actually, I wasn't thinking so much of Cary Grant's role in the movie, but the movie itself. Peter Lorre and Raymond Massey were incredibly funny in there, as were the other members of the cast. Grant was a leading man of the day who landed that role, and I agree, any number of others could have played it as well. It's the result of that cast that makes the film such fun. I see that there was a remake for TV with Lilian Gish and Helen Hayes. Bob Crane played Mortimer Brewster. Now there is an inspired job of casting. :/

SRS