Chance Ramsay, a riverboat gambler, has run into one too many sore losers; he s just killed a man in self-defense after winning the man s Arabian mare in a poker game in Georgia, and the man s brother vows revenge. Ramsay flees south into Florida, encountering young Josh Carpenter and his family, who are traveling into the Florida wilderness via wagon and riverboat to start a new life. Meanwhile, outlaws are gathering around the St. Johns River near the town of Volusia with plans to take the lands and livestock they want by force. Will the Carpenters and their companions prevail over those who would destroy their dreams even before they begin to build? Even with the help of Ramsay s blazing six-guns and the shrewd native skills of the trapper s daughter Abby Macklin, there will be "Thunder on the St. Johns" before this struggle reaches its final conclusion."