A daring team of marine engineers attempt to move a colossal British built Submarine 700 miles across water and land in Canada. The epic journey almost ends in disaster as the 1,400ton vessel topples over on a beach headland as it is hauled out of the sea onto dry land. The incident packed journey follows the team battling to haul the Cold War 'O'-Boat Onondaga across the stormy North Atlantic, through narrow locks and up a perilously steep railway to reach its final destination. Will they make it before winter blizzards strike?