After decades of hurricanes and oil spills in Louisiana, fisherman Thomas Gonzales faces a new threat: hordes of monstrous 20-pound swamp rats. Known as nutria, these invasive South American rodents breed faster than the roving squads of hunters can control them. With their orange teeth and voracious appetite, they are eating up the coastal wetlands that protect Thomas and his town of Delacroix Island from hurricanes. It’s man versus rodent.