Elise is a young French maiden, brought back to Scotland as part of the court of Mary, Queen of Scots. While her majesty is out on progress, Elise is left at Holyrood to learn better Gaelic and the customs of Scotland. When she is assaulted by her tutor, however, she refuses to remain in the castle any longer. She runs as far as she can before she collapses, feint from exhaustion.
She is awakened the next morning by the brutal sound of untuned bagpipes, their screeching and wailing driving her already pounding headache to new heights. It is here she is discovered by Duncan MacDonald, a poor student-turned-soldier, who comes across her whilst tuning his pipes. He takes her to his elderly grandmother, who agrees to care for the young and obviously frightened girl. Duncan and Elise slowly fall in love, despite the fact that Elise does not speak a word of Gaelic, and Duncan's French is rather sparse. They both manage somewhat decent English, but his is better than hers, and the language barrier makes life quite interesting.
They don't realize they are head-over-heels in love, of course, until he is called upon to fight for the queen. Shortly after he leaves, Elise's condition becomes blatantly obvious. Duncan returns to find her with a tiny baby and swiftly leaves in a fit of anger. He is stubborn, and believes only that Elise did not wait for him as promised. But Elise, too, is stubborn, and refuses to let him die because of a lie. She leaves tiny Marie (named for the queen, of course) in the care of her godmother and sets out to find him... equipped with a clamor and dirk, kilt, tartan, and the rest of the ensemble... she travels as a man, hoping to reach Duncan with more speed and agility. She is accepted into his regiment and pretends to be one of them... and Duncan can't help befriending "Angus." She has, by this time, learned to speak decent Gaelic and English, having spent the majority of the time when he was away pouring over his books, learning the ways of his people. Duncan and Angus become close friends, but when the leader of the regiment (Malcolm) discovers "Angus' " secret, he punishes her by taking advantage of her. Through this, all is revealed. Duncan blames himself for what happened to Elise, for the fact that she won't let him touch her, that she won't speak to him.
Eventually, however, she comes around to him. The love she has for him refuses to be hidden by her fear, and he realizes that the truly honorable thing to is not to leave her when he has doubts, but to marry her and show her what true love is after all.
