A woman on the edge of the sea finds a girl on the edge of life.
On the flooded coast of Cornwall, Ia Pendilly ekes out a fierce life in a childless marriage, as rough and stubborn as the sea. When a strange young girl washes up on the beach, Ia's rescue is only the beginning of a dangerous journey - one that will take them downriver, into the fringes of a collapsing society and for Ia, towards something she hopes might be love.