2. Ali's approach is incredible. There is nothing, just a faint plume of dust in the distance. Then a dot, barely visible, quivering, growing into a black figure floating alone on the horizon. Total silence, uncertainty. He is black, he comes like Death iteself. Who is he?
3. From the narrative side of things, this is a risky and fascinating way to introduce the film's #2 character, with whom we are supposed to sympathize. If Lawrence of Arabia were just an opposition between European and Arab, civilized and aspiring to civility, then this would be uninteresting. But it's a historical drama and its characters have depth and wit. Here we find the two sides of the dialectic which will drive much of the film, but their significance is ambiguous. How amazing to use all of these cues and not fall victim to them!
4. The dialogue is terse and expressive without giving itself away. We have been taught to like Lawrence's guide during the preceding scenes, so that we can be guaranteed to disapprove of the person who shot him. Lawrence need not gnash his teeth or scream or cradle the corpse. Instead he has a few brilliant lines: "My name is for my friends." "Then you would be a thief." It could scarcely be improved.