Extras/other people in the background are acceptable to meet the criteria but ideally with no human/entity on the screen at all that isn’t played by the same actor.
Movies like ‘Men’, ‘Moon’ or ‘The Nutty Professor’ don’t meet this criteria for example, due to the exceptions of characters played by other actors.
And it has to be somewhat mainstream and not a low budget student film or something.
Edit: I also meant that they play multiple characters…
Wikipedia says All is Lost has only 1 character, but I did find a SPOILER scene that shows Redford by someone else’s arm for only a couple of seconds. I’d figure this is the only scene with anyone else onscreen.
Here is an alternative Piped link(s):
SPOILER scene that shows Redford by someone else’s arm for only a couple of seconds
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