Captain Thomas Bartholomew Red and his first mate, Frog, are stranded aboard a raft at sea. Close to death from starvation and dehydration, Red tries to kill and eat Frog, but they are rescued by a Spanish galleon and are forced into slavery. Red inspires the slaves to mutiny and takes control of the vessel. Frog falls in love with the niece of a Spanish colonial governor, and unsuccessfully romances her. Red covets a golden throne that the Spanish have taken from an Aztec king. Through several adventures, Red recruits a crew of cutthroats to steal the throne. Despite their efforts, Red and Frog are ultimately stranded on a raft again, where Red sits on his golden throne and urges Frog to "fatten up".