The moon & the sun - Vonda N. McIntyre

In seventeenth-century France, Louis XIV rules with flamboyant ambition. In his domain, wealth and beauty are all; frivolity begets cruelty; science and alchemy collide. From the Hall of Mirrors to the vermin-infested attics of the Chateau at Versailles, courtiers compete to please the king, sacrificing fortune, principles, and even sacred family bonds.

'A wonderful book! Adventure, love, history, magic - it's an engrossing story with magnificent characters, balanced perfectly on the edge between,' said DIANA GABALDON

By the fiftieth year of his reign, Louis XIV has made France the most powerful state in the western world, but the Sun King's appetite for glory knows no bounds. In a bold stroke, he sends his natural philosopher on an expedition to seek the source of immortality: the mythical sea monster. For the glory of his God, his country, and his king, Father Yves de la Croix returns with his treasures: one heavy shroud packed in ice . . . and in a covered basin, an imprisoned sea-creature.

Marie-Josephe de la Croix has been looking forward to assisting her brother Yves in the scientific study of the sea monster,
until she makes a discovery that will threaten everything her brother, the court and the King believe.

'The finest alternate history ever, light-hearted and wise - a luminous, radiant novel,' said URSULA K. LE GUIN

But in the decadent court of King Louis, where morality is skewed and corruption reigns, will anyone listen to a single voice? Somehow, she must find the courage to follow her heart and her convictions - even at the cost of changing her life forever.