A moonbase crew fights for survival in the aftermath of a massive explosion that shifts the moon from its orbit into space.

The spaceship Altares, with a photon drive capable of accelerating it to the speed of light, leaves an Earth-orbiting space station. The Altares crew, two families of scientific specialists, journeys at light speed with time-dilation to Alpha Centauri, where they launch several satellites to transmit information on the Centauri star system back to Earth and guide future manned vessels in exploring.

Earth's Moon is the site of Moonbase Alpha, a scientific research colony nestled in the crater Plato. Staffed by over 300 men and women from Earth, it is the operations center for several space expeditions. It is also a watchdog for vast amounts of atomic waste from Earth stored in silos on the Moon's far side. Magnetic radiation builds up and causes the wastes to explode with such force that the Earth's centripetal pull on the Moon is overcome, and the Moon is broken free of Earth's orbit to drift at incredible speed out of the Solar System off the plane of the ecliptic. The survivors on Moonbase Alpha are unable to return to Earth and must survive in unknown space on their wandering Moon. They encounter a planet whose advanced people project an illusion of a devastating attack on Moonbase. This TV movie was edited from scenes of two episodes ("Breakaway" and "War Games") of "Space: 1999" (1975).

After an atomic explosion blasts the Moon out of Earth orbit, Moonbase Alpha drifts in space, with 300 people on board. When a rescue team from Earth arrives in a faster-than-light space ship, everyone is overjoyed that they can now return to Earth. But Moonbase Commander John Koenig, having undergone an experimental brain soothing process after receiving a concussion in a crash on the Lunar surface, sees not friends from Earth but gruesome monsters which have telepathically caused all others on Alpha to see an illusion of an Earth party. The aliens are desperate for radiation and plan to manipulate the Alphans into detonating nuclear waste on the Lunar surface, reducing the Moon and everyone on it to dust. Koenig must expose this conspiracy to save his people. Compiled from the two part episode The Bringers Of Wonder from the TV series Space: 1999's second series.

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.