The P-51 Mustang rose from obscurity to become the greatest long-range fighter in aviation history. Able to outfly even the best of the Axis aircraft, the Mustang decimated its enemies and drove them from the skies over Europe and Japan. But in it infancy, the Mustang flashed none of its war-winning potential. We trace the P-51's development from its origin through its re-emergence as the dominant aerial weapon of World War II.