The Borrowers live underneath the kitchen floor, whenever the Clocks need they simply "borrow" from the "human beans" who live above them. Only Pod ventures into the house above, Borrowers who are seen by humans are never seen again. But, Arrietty is seen, suddenly it seems everyone in the household is after the Borrowers, but have to put their trust in one human bean.

Thirteen-year-old Emily Starr, desperate to join her friends at high school in nearby Shrewsbury, agrees to Aunt Elizabeth's requirement that she stay in town with her Aunt Ruth, despite Ruth's refusal to allow Emily to follow her dream of becoming a writer.