England, January 1942: young Australian Ken Harding arrives at his first operational squadron, keen to play his part in the aerial attack on Germany as the commander of a bomber crew. Losses have been high and life expectancy is low, but Ken remains undaunted- until he meets his crew, a foulmouthed, battle-hardened bunch with no time for new boys who can't stand the pace. Together, they must take the war to the enemy over the most heavily-defended region of the Third Reich- the industrial heartland of the Ruhr, known to the men who face the flak and nightfighters as Happy Valley.