May 1959. From one side of St. Brigids Island, the mountains of Connemara are faintly visible on the distant mainland; from the other, the Atlantic stretches as far as the eye can see. This remote settlement, without electricity or even a harbor, has scarcely altered for centuries. Those who live there, including sisters Rose and Emer, are hardy and resourceful, dependent on the sea and each other for survival. Despite the islands natural beauty, it is a place that people move away from, not tountil an outspoken American, also named Brigid, arrives to claim her late uncles cottage.Brigid has come for more than an inheritance. Shes seeking a holy well thats rumored to grant miracles, but the islanders wont admit that it exists. Emer, as scarred and wary as Rose is beautiful and friendly, has good reason to believe in inexplicable powers. Despite her own strange abilitiesor perhaps because of themEmer fears that she wont be able to save her young son, Niall, from a growing threat. As months pass and Brigid carves out a place on the island and in the sisters lives, a complicated web of betrayal, fear, and desire culminates in one shocking night that will change the island, and its inhabitants, forever.