In Z for Zachariah there has been a nuclear explosion which

Burdon valley survived, as the valley is a nuclear enclave which means a place has its own climate, and Anne a girl who was left at home when her family went out in search of survivors, is convinced she is the only person left on earth. Anne is faced with a number of tough decisions as she strives to survive in a post-nuclear holocaust world. Then she sees a man coming! The smoke from a distance shatters Anne's solitude. She was so excited and wanted to go down and greet him, but then she thinks better of it and decides to camp out in the woods in a cave watching him.

Anne is a very cautious and intelligent girl which is shown by her knowledge or lack there of Mr Loomis. When he arrived...