The year is 1799. Admiral Caraccioli of Naples is about to be executed from the yard-arm of Nelson's ship in the Mediterranean. Young and in love with Caraccioli's daughter, the spirited French privateer, Raoul Yvard, and his wily sailing master, Ithuel Bolt, harass the British fleet against all odds. Yvard is captured but cunningly escapes, setting up a showdown at sea against the overwhelming forces of the Royal Navy.