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…
Bo Burnham: Inside?
Edit: I have since disavowed this instance
You’re right technically… but i should have said “fictional story” and “plays multiple characters”
The ones that come to mind all have other actors in the beginning or end, or voices from other actors. Locke, Buried, 127 Hours, Cast Away, Gravity…
IMDB tells me All is Lost lists only Robert Redford, but I haven’t seen it to be sure.
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.
Edit: I have since disavowed this instance
Buried, Ryan Reynolds is the only one on screen (not playing multiple characters, just one), though there are voiced characters from other actors on the phone.
I always forget about that movie, but it’s really good.
Not a film, but there’s a DC animated short where Mark Hamill voices every character.
I wouldn’t count anything that isn’t at least arguably as long as a movie. Wallace & Gromit: A Grand Day Out and the SpongeBob episode “Gary Takes a Bath” otherwise would count as well. There’s probably an otherwise qualifiable clone-focused episode of The Clone Wars, too.
Edit: I have since disavowed this instance
There’s a movie called “Love” that’s about a guy who gets stuck on a space station by himself after nuclear war breaks out. It used to be on Netflix but I’ve not been able to find it again after I watched it ten years ago.
