The story is set on a bucolic island off the coast of Maine in 1965. (Don’t worry about anachronisms; this is a fable, not history.) Two troubled 12-year-olds, Sam Shakusky (Jared Gilman) and Suzy Bishop (Kara Hayward), run off together and vanish into the wilderness. Sam is equipped with Indian-themed camping gear taken from his “Khaki Scout” troop. Suzy brings a kitten, a battery-powered record player and a suitcase full of juvenile fantasy novels. Though nobody realizes it, a major hurricane is bearing down on the island.
Sam’s scoutmaster Randy Ward (Edward Norton) takes charge of the search along with Captain Sharp (Bruce Willis) the lone police officer on the island. They are both well-meaning but the young scouts they deputize to help seem to be auditioning for roles in Lord of the Flies. Suzy’s parents (Bill Murray and Frances McDormand) are loud but ineffectual.
There are some scary moments (and a few that are cringe-inducing) but everything works out fairly well in the end.