The year is 1781 and Lady Mary Norton has been introduced into London Society. She has received several proposals but has refused all of them much to her mother and father's dismay. Mary is a strong character, fond of adventure and would rather have been born a boy. One of her three brothers, a midshipman in His Majesty's Britannic Navy, introduces Lady Mary to his friend and mentor, Lieutenant Charles Rufford, and Mary delights in the young man's company. But as the third son of a country squire he is deemed to be unsuitable as her prospective husband. "You are the daughter of an Earl and expected to make a good marriage befitting your station," her mother tells her. But Mary and Charles have fallen in love. What else can they do except elope?