The Borrowers opens as a young girl named Kate sits with Mrs. May, a woman who rents a room in Kate’s parents’ house in London. Kate is described as a wild and fearless child, and Mrs. May is a no-nonsense older woman with an air of confidence. Mrs. May teaches Kate many traditional homemaking tasks, from how to organize a drawer to how to properly wind a ball of yarn. She is also teaching Kate how to crochet. One afternoon, Kate mentions that she cannot find her crochet hook, which she left on a lower shelf near her bed the night before. Mrs. May looks alarmed and begins to tell Kate about the Borrowers, tiny people who live in the house and take things from humans. At first, Kate doesn’t believe her, but when she begins to think about how small objects often go missing and how she cannot find things like safety pins and blotting paper when she needs them, Mrs. May’s story takes on more credence.

Mrs. May insists that although she has never seen a Borrower herself, her brother did. She and her brother had been raised in India, but he was sent to live in a big old family home in the British countryside for a few months after coming down with rheumatic fever.