Moonbase Luna represents Earth's first Defence bulwark against the extraterrestrial threat, and is therefore one of the primary targets in attacks by UFOs. At the command of the fascinating Lieutenant Ellis, Base Luna is one of the most sophisticated facilities in SHADO, the secret organisation tasked with defending Earth from alien incursions.

Few people know of the chilling reality behind the mysterious phenomenon of unidentified flying objects. Beings from a dying planet have arrived on Earth to kidnap humans and take over their vital organs. Against this threat, SHADO has been created, a secret organisation equipped with the most advanced technology and the best men.

In 1980, the Supreme Headquarters Alien Defence Organisation (S.H.A.D.O.) is formed to protect Earth from an alien race that kidnaps humans and animals for their body parts. Operating from a secret base beneath a London film studio.

The Earth is threatened by an alien race who kidnap and kill humans and even animals and use them for their body parts. In the year 1980 S.H.A.D.O. (Supreme Headquarters Alien Defence Organization), a highly secret military organization, is set up in the hope of defending the Earth from this alien threat. This organization operates from a secret location beneath the Harlington-Straker film studio in London. S.H.A.D.O. also has a base on the moon with Interceptors as well as an early warning satellite that detects inbound UFOs (called S.I.D.), and operate a fleet of submarines. General James Henderson and commander Ed Straker have a team of highly trained and well equipped females and males to battle the regularly incoming hostile UFOs.