One of my favourite films especially the scene where Dustin Hoffman is strapped to the chair and in so many ways he's asked a range of questions with one line repeated by Sir Laurence Olivier,
"Is it safe?".
Did we ever find out what he was asking about?
Was it Diamonds... in the film?
Some years later, I watched a documentary about Sir Laurence Olivier and this included some interviews with the Great Man himself.
I was particularly interested when he started to comment on this particular film - The Marathon Man, because it included two of my favourites.
Sir Laurence Olivier explained the differences between the two actors, Dustin Hoffman (if I remember rightly) he said, ".. is a method actor..." and he went on to explain what he meant by that. Also explaining the difficulties he had to overcome during that scene. He said, "I had to say that one line over 50 times, that's the way it's written in the book." I think he said, "How do you translate that into the screen, by repeating one line 50 times?"
And then we were shown how the scene was played in the film. The interview continued after that scene ended and so Sir Laurence Olivier was explaining all this with it fresh in our minds.