Jonathan Pride is a mild-mannered dance instructor in 1820 Boston. En route to visit relatives, Jonathan is shanghaied by a band of zany pirates and forced to work as a galley boy. When the pirate vessel arrives at the port of Las Palomas, Jonathan, clad in buccaneer's garb, makes his escape. Everyone in Las Palomas, including Governor Alcalde (Frank Morgan) and fetching senorita Serafina (Steffi Duna), assumes that Jonathan is the pirate chieftain, leading to a series of typical comic-opera complications.