Trieste, 1867. Two petty criminals, Sarcany and Zirone, intercept a carrier pigeon. They find a ciphered message attached to its leg and uncover a plot to liberate Hungary from Austro-Hungarian rule. The two meet with Silas Toronthal, a corrupt banker, and form a plan to deliver the conspirators to the police in exchange for a rich reward. The three conspirators, Count Sandorf, Stephen Bathory and Ladislas Zathmar are arrested and sentenced to death. Fifteen years later, the renowned physician Dr. Antekirtt sets out to avenge those three brave men. Enlisting the aid of two French acrobats, Pescade and Matifou, he scours the Mediterranean in search of those who planned the betrayal. Rich beyond all imagination, wielding great power and master of an island fortress filled with advanced weaponry, Dr. Antekirtt will not rest until justice is done.