The film is set in the 1960s on a small island off the coast of New England, where a young boy named Sam Shakusky (Jared Gilman) and a young girl named Suzy Bishop (Kara Hayward) form an unlikely bond. Both Sam and Suzy are outsiders in their own way, struggling to find their place in the world. Sam is an orphan who lives in a foster home, while Suzy is a free-spirited girl who feels suffocated by her family and community.