The Conspirators is a novel written by Alexandre Dumas and Auguste Maquet, published in 1843. Dumas reworked a preliminary version by Maquet; this was the beginning of their collaboration which was to produce eighteen novels and many plays. The dramatisation of the novel – in five acts, a prologue and ten tableaux – was first performed on 16 July 1849 at the Théâtre-Historique in Paris. It was adapted into an opera, Le chevalier d'Harmental, by André Messager with a libretto by Paul Ferrier, which was first performed on 5 May 1896.