11-year-old Grey just crawled back out of her grave after having died of the Bubonic Plague over four-hundred years ago, with the strange discovery that she can no longer die. She wanders the streets of a small town in England, alone, cold, and confused, until a man shows up who claims to have been looking for her. She is questioned, and taken back to a facility known as "The SCP Foundation". Many strange creatures are housed there, and she even meets a few kids there about her age that all share one similarity: they're not normal. Grey goes on to befriend many, both staff and SCPs alike, even encountering someone she'd yearned to reunite with.