Libby Snow has always felt the pull of Ullaness, a headland on Scotland's sea-lashed western coast where a legend has taken root. At its center is Ulla, an eighth-century Norsewoman whose uncertain fate was entangled with two warring brothers and a man who sought to save her. Libby first heard the stories from her grandmother, who had learned it from her own forebear, Ellen, a maid at Sturrock House.

The Sturrocks have owned the land where Ulla dwelled for generations, and now Libby, an archaeologist, has their permission to excavate a mysterious mound, which she hopes will cast light on the legend's truth. But before she can begin, storms reveal the unexpected: the century-old bones of an unidentified man. The discovery triggers Libby's memories of family stories about Ellen, of her strange obsession with Ulla, and of her violent past at Sturrock House.

As Libby digs deeper, she unravels a recurring story of love, tragedy, and threads that bind the past to the present. And as she learns more of Rodri Sturrock, the landowner's brother, she realizes these forces are still at work, and that she has her own role to play in Ulla's dark legend.