In the 17th century, long before modern science and in a time of great fear of the unknown, the villagers of a small coastal community find themselves drawn to, and suspicious of, Morag, a remarkable but mysterious woman who is uniquely connected to the nature that surrounds her. Survival is a daily and all-consuming struggle that is thinly forged from an inclement sea and pushed to the edge of the land by merciless feudal landowners. But it is Morag's passionate relationship with John Tullock, who is unwittingly pledged to marry Sinéad, that threatens to tear the community apart.