1960. The height of the Cold War. Maths prodigy Ginny Matlock is appointed to be the first woman computer at a secretive nuclear testing facility off the East Anglian coast. She quickly finds, in this landscape of endless skies and shifting shorelines, that nothing is what it seems. What is the terrible secret of Briar Cottage? What dark tale haunts the local pub? And who is the mysterious Artist with whom Ginny's fate becomes entangled? As the Berlin Wall rises and nuclear armageddon threatens in Cuba, can Ginny build a life for herself among so many mysteries or will the terrors of the age suck her under?