The story "Time Enough at Last" is a science fiction short story written by Lynn Venable. It was also adapted into an episode of the television series "The Twilight Zone."
The story is set in a post-apocalyptic world after a devastating event, which is not explicitly described in the story. The protagonist, Henry Bemis, is an avid bookworm who works at a bank. The story primarily takes place in Henry's workplace, the bank's vault, where he seeks solace and privacy to indulge in his passion for reading during his lunch breaks.
After an incident that leads to Henry being trapped in the vault, he emerges to discover that the world around him has been destroyed. The city is in ruins, and he is the only survivor. The setting shifts between the vault, where Henry spends a significant portion of the story, and the desolate wasteland that was once a bustling city.
Overall, the story "Time Enough at Last" is set in a post-apocalyptic world, with the majority of the events taking place in a bank vault and the surrounding ruins of the city.