The story is set in Paris of the early 20th century.

Florian Rochefort is the only son of an impoverished aristorcratic family and becomes Ray Balzac Courland's collateral in exchange for the loan the pawnbroker pays to Florian's mother so she can amortize some of the family's depts. But in fact Ray is the infamous thief Noir who, having a special liking for extraordinary jewels, couldn't but claim Florian's outstanding amethyst eyes for his collection.

As the story unfolds the reader follows the protagonists on their adventures in France, Morocco and Tunisia while their relationship deepens.