Moonrise Kingdom is set in 1965 on an island off the coast of New England.
It's the end of the summer and the seasonal hurricanes loom on the horizon.

Set against this background is a romance between two twelve-year-olds: Lucy Bishop, (who lives on the island with her parents [Bill Murray and Frances McDormand] and three younger brothers) and Sam (an orphan who is camping on the island with the Khaki Scout troop).

Lucy and Sam hatch a secret plan to run away, and undertake a perilous journey though the woods and across the streams that criss-cross the island, to an isolated cove, where they set up their kingdom. They are pursued by the local sheriff (Bruce Willis) and the scout troop leader Scout Master Ward (Edward Norton).

The follies of youth are matched by the compromises of age, and as the conflict between the generations escalates, the hurricane breaks upon the island putting all the characters at risk...