Helen Dunmore

“An unconventional thriller [and] a page turner . . . As much a surprising love story as it is a tale of spies” (The New York Times Book Review).
 
In 1960 London, the Cold War is at its height, and a spy may be a friend or neighbor, colleague or lover. Two colleagues, Giles Holloway and Simon Callington, face a terrible dilemma over a missing top-secret file.
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As they search for their missing father near their Cornwall home, Sapphy and her brother Conor learn about their family's connection to the domains of air and of water.

Two years after the disappearance of their father, Sapphire and Conor, having moved with their mother to the town of St. Pirans, try to make a new life for themselves, but Sapphire, unlike her mother and brother, finds it increasingly difficult to adjust to her new circumstances and is drawn more and more to the undersea world of Ingo.

In this companion novel to the Ingo series, myth and reality collide when Morveren, a young girl from a Cornish island, discovers a Mer boy, Malin, half-buried in the sand dunes. New conflicts erupt between the worlds of sea and air, and storm clouds of danger gather as Morveren and her twin sister, Jenna, struggle to protect Malin. An enthralling battle of loyalties begins when Morveren and Jenna learn that even your closest friend can betray you,...