I discovered a concept community for doomsday preppers called the Citadel. It is a community that is designed to withstand the end of the world. I am thinking of writing a novella about a similar community of doomsday preppers. I am thinking of watching shows and documentaries as inspiration of how such a community would operate. However, my story will depict the community having to deal with a siege from an inhuman enemy. The irony is that they have been preparing for the end of the world and they finally got their wish.