In 1700, the pirates of Madagascar menace the India trade; British officer Brian Hawke has himself cashiered, flogged, and set adrift to infiltrate the pirate "republic." There, Hawke meets lovely Spitfire Stevens, a pirate captain in her own right, and the sparks begin to fly; but wooing a pirate poses unique problems. Especially after he rescues adoring young Princess Patma from a captured ship. Meanwhile, Hawke's secret mission proceeds to an action-packed climax.

Geoffrey Thorpe (Errol Flynn) is an adventurous and dashing pirate, who feels that he should pirate the Spanish ships for the good of England. In one such battle, he overtakes a Spanish ship, and when he comes aboard, he finds Doña Maria (Brenda Marshall), a beautiful Spanish royal. He is overwhelmed by her beauty, but she will have nothing to do with him because of his pirating ways (which include taking her prized jewels). To show his noble side, he suprises her by returning the jewels, and...