Cell phones would have radically altered the story
Now granted, I have only seen the Hepburn movie and not the play or any more modern versions that may exist, but I felt that this was a story that would be hard to tell if cellphones existed.
1. The bad guys would not have needed to use the phone booth. Rather they could have called each other's phones instead to cover their tracks.
2. Further, since they would have used cellphones Susy could not have seen where the calls were being made from, meaning that they might not have figured out who was behind what.
3. The villains could not have easily disconnected the blind woman from the outside world, because even with the landline cut she could have used, you guessed it, a cellphone. Maybe it seems strange to some to think that someone blind would have a cellphone, but since the big theme is Hepburn's character becoming independent it would not have been impossible.
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