Eilidh Campbell returns to her Scottish roots from America with one main aim: to discover the identity of her real father. But her mother's past in Inverclyde is a mystery with family secrets, a book of Robert Burns' poems containing a hidden letter and a photograph link to the Holy Loch at Dunoon when the American Navy were in residence.

Staying with her childhood friend, Kirsty, while searching for answers, Eilidh begins to fall in love with handsome Scot Lewis Grant, but how free is he? Together they trace the story of Highland Mary and Robert Burns, with its echoes to her mother's story, and Eilidh finds the past is closer than she realises. Highland Mary tells her own ill-fated story from the eighteenth century in alternate short historical chapters.