Wing commander Guy Gibson learns that he has less than eight weeks to recruit and train 147 aircrew for a top secret mission.

Dan Snow relives the daring bombing raids. To get his revolutionary new bouncing bomb to work, Barnes Wallis has to create an entirely new aiming device.

Dan Snow relives the daring bombing raids. The raid on Germany's dams gets off to a rocky start. Maltby and his crew finally release their bomb.