At the age of thirty-five, Fanny van de Grift Osbourne has left her philandering husband in San Francisco to set sail for Belgium to study art, with her three children and nanny in tow. Not long after her arrival, however, tragedy strikes, and Fanny and her brood repair to a quiet artists' colony in France where she can recuperate.

There she meets Robert Louis Stevenson, ten years her junior, who is instantly smitten with the earthy, independent, and opinionated belle Americaine.

A woman ahead of her time, Fanny does not immediately take to the young lawyer who longs to devote his life to literature rather than the law - and who would eventually write such classics as Treasure Island and The Strange Case of Dr. Jekyll and Mr. Hyde. In time, though, she succumbs to Stevenson's charms, and the two begin a fierce love affair-marked by intense joy and harrowing darkness that spans decades as they travel the world for the sake of his health following their art and dreams eventually settling in Samoa where Robert Louis Stevenson is buried, with these words on his grave:

Under the wide an starry sky,

Dig my grave and let me lie,

Glad did I live and gladly die,

And laid me down with a will,

And this be the verse that you grave for me,

Here he lies where he longed to be,

Home is the sailor home from the sea,

And the hunter home from the hill.