“I've got something I want to say right up front,” says Boone McCallister, as he speaks into an Edison Dictaphone in 1937, “and that is that I did not feed David Klee to an alligator. That damned rumor has hounded me my whole life.”

Back in 1864, with his father gone to fight for the South, young Boone embarks on a cattle drive with the McCallister’s Flat Iron Ranch in pioneer Florida, sending a herd of cattle to the Gulf port south of Tampa. Besides navigating dangerous cattle country, the headstrong, naïve Boone encounters vengeful Yankees, orders a hanging, braves alligators, and comes into contact with a group of swamp outlaws, the Klees, which begins a costly feud between the two families.

When the Klees pillage and set fire to the Flat Iron Ranch, they also kidnap a comely slave girl, Lena. Against the odds, Boone must lead an operation to get her back, leading to a showdown in the middle of unfamiliar and unsettled outlaw territory that would one day become Miami.