Air-Sub "DX" was the invention of Professor Gray. It was a flying submarine equipped with a "dissolving gun".Professor Gray and his lovely daughter Rita form the team in charge of Air-Sub "DX" together with strapping Captain Tim, the Professor's lab assistant who becomes the de facto captain of the Air-Sub as well as a somewhat costumed adventurer. The Air Sub team fought Curley, a dictator of an undersea kingdom, was constantly trying to steal this vehicle to use as a super-weapon in his wars of conquest.