The 16th century, the Malabar Coast. General Barbosa (KN Singh) signs a treaty with the queen (Sulochana) of a small state giving the Portuguese right to trade in exchange for military protection. With the help of the queen's nephew Jaswant (Ramsingh), he begins to meddle in the administration as well. He arrests merchant Ramzan Ali and his friend Narayan Das. Das' daughter Nisha (Geeta Bali) tries to save her father but is caught by Barbosa and both are sold to a cruel Portuguese pirate Cabral. Cabral kills Narayan Das. Nisha rouses her fellow slaves to revolt against Cabral and once Cabral is killed Nisha becomes a pirate queen pillaging all Portuguese ships in sight. One such ship includes heir to the throne Prince Ravi (Guru Dutt), a Portuguese woman Rosita (Kuldip Kaur) and a court astrologer (Johnny Walker). Nisha spares their lives as Ravi had saved her life earlier. They inevitably fall in love. Ravi joins the mutineers without revealing his identity. Back on shore, Ravi learns Jaswant is to be crowned king. Ravi is arrested and sentenced to death. Nisha saves him and they join forces with other local chiefs to defeat Barbosa.