Guinevere has traveled to Paris to have a dress designed by the famous but neurotic Antoine de la Poulet. Insisting on the very best material, King Arthur is dispatched to a tropical jungle to retrieve the rare blood-sucking silk worms of Rangoon. Meanwhile, the French peasants are having one of their many revolutions and, on his return with the worms, the King discovers that Guinevere has been taken to the infamous tower prison known as the Pastille! The rescue attempt fails and Merlin, the King and his beloved Princess are carted off to their executions. Only Sir Margaret can save them – but will she bother?