Fulvio is a revolutionary in early nineteenth century Italy. He seeks refuge in his father's villa and he is joined there by his girl-friend, Charlotte. But his plans for a new life are frustrated by the arrival of a group of revolutionaries who involve him in a plot for an expedition in Southern Italy. Fulvio betrays them to the police; Charlotte is wounded in the melee, but the surviving plotters continue with their plans. Fulvio betrays them again, killing Lionello, his closest friend, and stealing the money that had been entrusted to him for the purchase of arms. He seduces Mirella, Lionello's girl, pretending to be in love with her in order to avoid being denounced.

The group land in the South, and Fulvio makes one last attempt to sabotage their efforts. He circulates a rumour among the local villages that they are a band of robbers seeking plunder. The revolutionary scheme fails, but Fulvio is caught by the plot he has himself engineered.