In The Grand Duke Gilbert and Sullivan come full circle back to the theme of their first collaboration Thespis: a troupe of actors taking political power. The plot hinges on the mis-interpretation of a 100 year-old law regarding statutory duels (decided by drawing cards). The baffled central character Ludwig becomes engaged to four different women before the plot is resolved. The frugality and phoniness of the wealthy classes and the nobility is lampoone.
