The repetition of that phrase frames this scene that ends of course with Iago’s vow of double knavery against The Moor. I can watch Branagh over and over as Iago or Hamlet. He goes to so many levels, dances and descends, and always seems to be in the moment, reacting to Roderigo as his weaknesses become apparent, as the moment develops, like a true sociopath, always fixated on the objective that is buried deep, protected.