She stopped dead and turned her frown towards him. “What do you mean?”

“I mean he borrowed, or stole, that identity off a dead boy from Harris. His name was actually Donald John Gillies, and he came from the Isle of Eriskay. The young man they took out of the bog was his brother, Donald Peter.”

Marsaili gaped at him in disbelief.

“Only Donald John isn’t his real name either.” He saw her whole world falling apart in the look of pain that creased her eyes. All the certainties of her life shifting beneath her feet like the sand she stood on.

“I don’t understand . . .”

And he told her everything that he had learned, and how he had learned it. She listened in silence, her face paler than the moon, and in the end put a hand on his arm to steady herself.

“My dad was a homer?”

Fin nodded. “An orphan in all probability. Or a child in care, shipped out to the islands with his brother by the Catholic Church.”

She slumped down into the sand, sitting cross-legged, her face falling forward into open hands. At first he thought she was crying, but when she took her face out of her hands it was dry. Shock had blunted all other emotions. Fin sat down beside her. She gazed out over the transient benevolence of the sea and said, “It’s strange. You think you know who you are, because you think you know who your parents are. Some things are just . . .” she searched for the word “. . . unquestioned, unquestionable.” She shook her head. “And then suddenly you learn that your whole life has been based on a lie, and you’ve no idea who you are any more.” She turned to look at him, eyes wide with disillusion. “Did my dad kill his brother?”

And Fin realized then that while for him it might be possible to accept the idea that her father’s true origins and who murdered his brother might never be discovered, Marsaili could not rest until she knew the truth. “I don’t know.” He put an arm around her and she rested her head on his shoulder.

They sat like that for a long time, listening to the slow, steady pulse of the ocean, drenched in moonlight, until he felt her trembling with the cold. But she made no attempt to move. “I went to see him, just before I left for Glasgow, and found him sitting in the rain. He thought he was on a boat. The Claymore, he said it was, sailing from the mainland.” She turned to look at Fin, her eyes clouded and sad. “I thought he was just rambling. Something he’d seen on television or read in a book. At first he called me Catherine, and then Ceit, like I was someone he knew. Not his daughter. And he talked about someone else called Big Kenneth.”