In cold, murky water, working by touch alone, they can defuse a mine powerful enough to sink a battleship. Under the burning Afghan sun, they can dismantle a Taliban roadside bomb. Welcome to the world of the Royal Australian Navy clearance divers. Bomb and mine disposal is but one of their roles. As covert swimmers they can infiltrate enemy waters. As boarding parties they are on the anti-piracy frontline. As counterterrorist special forces they are on call 24/7. They are simply one of the best diving units in the military world. Their story goes back to the Second World War, when Hitler's secret weapon - the magnetic mine - had Britain on her knees. Four extraordinary Aussies were among the brave naval volunteers who tackled Nazi mines on land and under water. The men who followed their path share the same brand of courage. From the rivers of Vietnam to the deserts of Afghanistan, navy divers have excelled under the most dire pressure, yet we know very little of their heroic deeds. Their incredible story has remained behind closed doors. Until now . . .