Pod and Homily Clock and their sixteen year old daughter Arietty are 'Borrowers', four inch high people who live under the floor boards in Granny Driver's house and borrow what they need without her knowledge. She is determined to catch them. When Arietty defies her father and strays into the house alone young James hides her and they become friends but Granny contacts Professor Mildeye,who is obsessed with the existence of 'Homo Sapiens Redactus',whom he wants to exhibit to the world and he captures Pod and Homily. Fortunately Arietty and resourceful fellow Borrower Spiller join forces with James to effect a rescue before the professor can dissect his tiny captives.