Something bad happened to the vault dwellers
A thing to understand about Vault-Tec: the vaults they promised would keep people safe through the apocalypse were also a ploy for the company to find willing lab rats on which to conduct fucked-up experiments. Some of these are truly awful, others are kind of hilarious. Almost every vault has some story like these, and it seems like we’re going to see what horrible happenings are going on in Vault 4 this season.
