The dialogue-less animated film follows the major life stages of a man castaway on a deserted tropical island populated by turtles, crabs and birds.

In a secret world hidden beneath the floorboards, little people called Borrowers live out of sight of humans. But when brave and tiny Arrietty is out gathering supplies, she is discovered by Shawn, a human boy. They begin to form a friendship that blossoms into an extraordinary adventure.