How did the U.S. Navy—the branch of the U.S. military tasked with patrolling the oceans—ever manage to produce raiders trained to operate on land? And how, against all odds, did that unit become one of the world’s most elite commando forces, routinely striking thousands of miles from the water into the battlefields of Iraq, Afghanistan, Syria, even central Africa? Behind the SEALs’ improbable rise lies the most remarkable underdog story in American military history—and in these pages, former Navy SEAL Ben Milligan captures it as never before. Told through the eyes of remarkable leaders and racing from one longshot, hair-curling raid to the next, it’s a tale of the unit’s heroic naval predecessors, and the evolution of the SEALs themselves.