There are actors. They learned acting. In school, over years and they play a role. Than, Hollywood created the Character Actor. That's fascinating personalities that put into a certain, specific role naturally fill out that character, having no major acting degree.
That concept turned out to be superior to classic actors and when both meet the best movies come down.
Now imagine two things:
What do you expect from a movie starting exactly like this short? Just be honest.
Then, imagine she has no idea what's gonna happen, but only that she will be save, only blanks will be fired and the shots taken are long letting her dissolve into the scenario.
That means, going back closer to Theater, you break down the scenes and locations. Set up several cameras and let it role. Improvisation. Then, you remake all that went too wrong and the rest is between cutter and director.
