A French-language version, translated and adapted by Charlotte and Marie-Louise Desroyses, was also produced under the title Nouveaux Exploits du Mouron Rouge.

The plot is hatched at a gala on Richmond Green, with the help of a young French actress, Désirée Candeille, whom Chauvelin has enlisted with promises of money, pardon and fame if she succeeds.

On discovering her to be a fellow French actress, she is soon taken in by the young woman's sob story and before long had invited her to perform at her house in Richmond in front of the Prince of Wales.

Chauvelin has managed to get his hands on her family jewels (which were being looked after by the local priest) and has given a diamond necklace, which belonged to Juliette's mother, to Désirée Candeille.

Désirée manages to engineer the situation so that Sir Percy must fight Chauvelin in a duel to avenge the insults levied against her—for which they must go to France, as duelling is outlawed in England.