After a near-suicide mission to the Swartfjord, which claimed many lives, morale among the survivors of 633 Squadron was at its lowest ebb. Unbearable tension and problems with replacement recruits were tearing the squadron apart...

The new Commander, Ian Moore — young, brilliant and aggressive — knew that the only thing that would pull it together was the challenge of another dangerous mission...

The Germans were developing “Rhine Maiden,” a new antiaircraft rocket which posed a deadly threat to the Allies’ invasion plans. So the top brass decided that 633 Squadron should first bomb the rocket factory and then make a daring strike in broad daylight on an underground target buried deep in a Bavarian valley...