The Dambusters

24-year-old wing commander Guy Gibson has less than eight weeks to recruit and train 147 aircrew for a top-secret mission; they are required to learn to fly at super-low altitudes at night toward targets on water.

Wallis tries to get his revolutionary bouncing bomb to work, which will require the invention of a new aiming device; Dan Snow takes to the skies to test it, but accuracy isn't the only problem.

The raid on Germany's dams gets off to a rocky start as the crews struggle to clear the airfield in their planes loaded with four-tonne bouncing bombs; out of the 133 young men who flew on the raid, only 80 survive.