The narrative moves back and forth through time, showing readers Grainne as a child, as a young woman, and as a mature woman--which gives readers a multidimensional picture of Grainne. The narration alternates, in other words, from the point of view of maiden, mother, and matriarch.
By including the childhood scenes, readers can see how the young Grainne developed her passion for the sea. The more her father tries to dissuade her from following in his footsteps, the more she insists on becoming proficient in seamanship. Readers see the young Grainne cut off her hair in defiance when she is not allowed to go to sea.
As a young adult, she goes to Rockfleet Castle for fosterage where she meets the dashing Richard Bourke. Grainne laments that she is not in charge of her own destiny. The young Grainne tells those who marry her against her will:
"I want Spain and France and Portugal. I want a boat of my own. And a life bigger than any tower house can hold."
Despite these protests, Grainne's beloved father marries her off to Donal O'Flaherty. Grainne suffers in this loveless marriage, yet she begins to gain acclaim as a leader. Her rise to Chieftain or Taoiseach was still far from easy. After her husband dies, Grainne fights off the Joyces to regain Castlekirk. Afterwards, she has to battle Rory, who has taken over Bunowen Castle in her absence and declared himself Chieftain.
The mature Grainne has even more problems. She is waylaid and imprisoned by Sir Richard Bingham in Dublin Castle. Bingham kills many of her relatives, including her son, before, miraculously, Elizabeth I's spymaster secures her release.
To exact her revenge against Bingham, Grainne entices the Gallowglass, a mercenary Scottish army, to pursue his men. For the first time, she ignores the "Sense"--the ability to sense dangerous storms. This, unfortunately, leads to the loss of many ships off the coast of Ulster.