Awesome take on it! I was thinking something like “High Rise” where their society starts to fall apart. And Abba’s gonna be stuck in my head all day now, thanks!
I heard about this complex as well, my first thought was “well, unless they’re in driving distance of the bunker, they’re not getting in.” Realistically, any scenario where you would need to take cover would pretty much ground all flights and clog up the interstate. You could do a whole race against time thing with a family trying to navigate through the chaos in order to get to the bunker. Nice and cheap!
Another thought: why is society collapsing? And why are the rich so afraid of the collapse? Because they’re causing it. Greed is the seed for so much of what’s wrong with the world, you can find its’ fingerprints in everything, so they make the mess and they don’t want to clean it up. So that’s territory to explore. Maybe someone goes self-righteous, maybe we see greed destroy them all over again.
And this whole idea of living in a concrete box for five years with a bunch of strangers, unable to leave, unable to see sunlight? Sounds like prison. Maybe the whole thing is a Twilight Zone-esque con, a silent uprising/coup: convince the rich and powerful society’s coming to an end (Wag The Dog-style), have them all retreat to one place for safety, and exact punishment.