Starting in the 1930's, Japanese aircraft designers made incredible strides and by the time hostilities broke out, the Imperial Air Force and Navy had some of the most sophisticated planes in the world.

This programme traces the development of the Japanese industry and its famous creations like the Nakajima K1-43 Oscar and the Mitsubishi A6M Zero, but the programme also exposes the frantic, top-secret programs to produce weapons that would have made these legendary planes seem tame by comparison - Helicopters, jet-bombers, rocket fighters and a huge, long-range aircraft designed to strike directly at the US west coast with biological weapons. We tell for the first time how the plans for Nazi jet and rocket aircraft were taken to Japan by submarine and how the Japanese converted these designs for their own use.

Using specially commissioned computer graphics, never seen archive footage and interviews with aviation experts, we bring back to life the Secret Japanese Planes of the Second World War.