In late 18th century, Marianne Flambelle is a fifteen years old girl who back La Rochelle, France, after a travel across USA together her uncle Jacques, a friend of La Fayette, in order to find Marianne's parents. But in the fight between monarchical and republican after French Revolution that changed the country, Marianne's parents miss. Brave swordswoman and captain of her own ship, Marianne works for Intelligence French to support the new France with help of her uncle Jacques and her crew. Therefore, an evil character named Courtard is determined to destroy Flambelle family and follows Marianne with all his hate in an attempt to locate the same fabulous treasure that Marianne tries to find, and that it was hidden by Marianne's father, a famous weapons manufacturer, after it was given him by an immigrants time ago.