Greg Townsend is building a shuttle vehicle from an old F-4 Phantom, and launching it from a Boeing 707. What he doesn't know is that a secret government committee is bent on stopping him. On the first flight, the craft has a massive pressurization failure. Townsend and his old comrade from the Navy, Mitch Silvera land the stricken craft. Then the plot emerges. Will the shadow enemy win?