The world's coming to an end. Your small city is one of the last remaining pockets of uninfected humans on the planet. The walls around it were constructed by a goverment refief agency to keep whatever caused this out, but the only purpose they seem to serve now is keeping everyone in and driving them mad. Those that do pass the walls, never come back.
The Father, a single parent and double amputee, has been protecting and raising The Child for months in this walled-off city. Dealing with the loss of his wife and The Child's sibling six years ago had been difficult enough without the neighbors going feral and seemingly supernatural creatures roaming the streets.
Last night he failed. She was taken from him.