Episode 7, "Missing Link": Commander Koenig's soul is captured after his eagle crashes and is scrutinized by an alien on the planet Zenno, where humans appear to be their missing link. Guest star: Peter Cushing.
Episode 8, "The Guardian of Piri": The planet Piri is discovered to be hospitable to humans, promising a potential home for the wandering Alphans. But there's a catch: on Piri, humans are lured by the promise of eternal, zombie-like happiness, and only Koenig knows how to rescue his crew from their hypnotic captivity. Guest star Catherine Schell would later join the regular cast as Maya.
Episode 9, "Force of Life": Technician Anton Zoref becomes possessed by an energy being that feeds on heat, making everyone on Alpha a target to its icy touch of death. As the body count rises, Koenig must order that Zoref be killed... But will his orders be carried out in time to save Alpha?
Episode 10, "Alpha Child": Unto Alpha a child is born, but soon joy will change to fear as every Alphan must bend to the will of its newest resident. The newborn swiftly transforms into something totally unexpected...the leader of an alien invasion.
Episode 11, "The Last Sunset": A miracle has happened: the moon has an atmosphere, which has been emitted by a satellite from the nearby planet Ariel. It seems as though Alpha will become a permanently habitable home for its human occupants--but will this surprising gift signal the final days of Moonbase Alpha?
Episode 12, "Voyager's Return": Sent from Earth years ago, the Voyager One probe is returning to Earth propelled by its innovative "Queller Drive." The probe's memory banks provide valuable data for Moonbase Alpha, but a fleet of alien ships arrives to condemn all of humanity for unleashing the "Queller Drive" as a destructive force in the galaxy.
- Director: Bob Brooks (III)
- Director: Kevin Connor
- Director: Robert Lynn (II)
- Director: Val Guest
- Aspect Ratio: 1.33:1
- Audience Rating: NR (Not Rated)
- Format: Box set, Color, DVD-Video, Full Screen, NTSC
- ISBN: 0767032357
- Language (Original Language): English
- Region Code: 1
- Release Date: 2001-01-30
- Running Time: 312 minutes
- Theatrical Release Date: 1975-09-05
