An aircraft designer struggles to create a new kind of fighter plane to take on the Nazis.

By the late 1920's aircraft designer R.J. Mitchell feels he has achieved all he wants with his revolutionary mono-planes winning trophy after trophy. But a holiday in Germany shortly after Hitler assumes power convinces him that it is vital to design a completely new type of fighter plane and that sooner or later Britain's very survival may depend on what he comes to call the Spitfire.