This is a tale of human obsession, one intrepid tuna, the dedicated fisherman who caught and set her free, the promises and limits of ocean science and the big truth of how our insatiable appetite for bluefin transformed a cottage industry into a global dilemma. In 2004, an enigmatic charter captain named Al Anderson caught and marked one Atlantic bluefin tuna off New England’s coast with a plastic fish tag. Fourteen years later that fish – dubbed Amelia for her ocean-spanning journeys – died in a Mediterranean fish trap, sparking Karen Pinchin’s riveting investigation into the marvels, struggles, and prehistoric legacy of this remarkable species. Over his fishing career Al marked more than sixty thousand fish with plastic tags, an obsession that made him nearly as many enemies as it did friends. His quest landed him in the crossfire of an ongoing fight between a booming bluefin tuna industry and desperate conservation efforts, a conflict that is once again heating up as overfishing