A United States Navy ship in the first half of the 19th century, under the command of Captain David Porter, is expecting to put ashore after a year on the seas; but the arrival of one of Porter's ex-students, the willful and independent Lieutenant David Farragut, brings a new mission: to disguise the ship and crew as a pirate ship and help the Navy locate the criminals who have been robbing America's merchant fleet. But as Farragut's disobedience threatens the safety of the crew, they stumble upon an international conspiracy.