The Borrowers Aloft — Mary Norton

Pod, Homily, and Arrietty Clock -- the family of tiny Borrowers -- think they have at last found an ideal home. They've moved into a house in a miniature village built as a hobby by a retired railroad man. The village is the perfect size for Borrowers, and after the hardships they've faced, the Clocks gratefully settle into the luxury of having a "proper" house. The easy life makes them careless.

Or rather, it makes Arrietty careless. She befriends a "human bean," and the next thing Arrietty knows, she and her family have been kidnapped. Their captors are a greedy married couple, called the Platters, who have big plans for the little people. They have created their own miniature village in a glass case and plan to imprison the Borrowers within -- like animals in a zoo -- for the rest of their lives.