Around 1970, the British and American governments receive incontrovertible 
evidence that aliens exist and are abducting humans. 
In cooperation with the United Nations, they set up a secret worldwide 
organization, SHADO (Supreme Headquarters Alien Defence Organisation), which 
operates in the 1980s. 
With resources and equipment under the seas, in the air, on land, in orbit and 
on the Moon, SHADO's purpose is to stop the alien incursions and find out why 
the aliens want humans