The Queen's Necklace is a novel by Alexandre Dumas that was published in 1849 and 1850 (immediately following the French Revolution of 1848). It is loosely based on the Affair of the Diamond Necklace, an episode involving fraud and royal scandal that made headlines at the court of Louis XVI in the 1780s.
The novel first appeared in serialised form in La Presse. The story takes place between 1784 and 1785. It is the second in a series of four novels focused on the character of Cagliostro, presented by Dumas as the man pulling all the strings of the affair.