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A fictional top-secret human organization from the UFO TV series from the early 1970s.
S.H.A.D.O. (Supreme Headquarters, Alien Defense Organization) is a hi-tech secret armed group created to defend the Earth from an alien invasion.
SHADO has a variety of advanced hardware and vehicles at its disposal to implement a layered defense of planet Earth. Early warnings of alien attack would come from SID, the Space Intruder Detector, a computerized tracking satellite that constantly scans for UFO incursions.
The forward line of defense is Moonbase from which three Lunar Interceptor spacecraft, carrying nuclear missiles, are launched.
The second line of defense includes Skydiver, a submarine mated with the submersible, undersea-launched Sky One interceptor aircraft, which attacks UFOs in Earth's atmosphere.
The last line of defense are ground units including the heavy armed and armored, IFV-like SHADO Mobiles, fitted with caterpillar tracks.
Lt. Gay Ellis is a notable member of the group.
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