Two years after the death of his wife, long-time summer resident Harry Richardson decides to sell his family home on Little Great Island in Maine.

Yet everyone has a different idea of what that land might become. Mari, the feisty and outspoken woman Harry is beginning to care for, desperately wants to farm the land in a way that could sustain her own family while also serving as a working model for the island's economic future, which is threatened by the impact of climate change on lobster fishing. Problem is, she needs every penny she can earn to fight for custody of her son.

Meanwhile, Harry's siblings, who are co-owners of the property, are in favor of a quick sale; Frank Clatcher, the island's primary business owner, wants Harry to sell to a developer, thereby increasing tax revenue and his own family's fortunes; and retired statesman Tom Estabrook, the island's "grand old man" pushes for the land to be put into a conservation easement to protect it for future generations. As the conflicting visions of Little Great Island's future take hold, the fragile balance between the island's native population and summer visitors fractures as everyone fights for their own view of the future. Only when tragedy strikes can the community reunite and find a way forward.