"Devil's Planet" is the twenty-second episode of the second series of the British sci-fi television series Space: 1999 (and the forty-sixth overall episode of the programme). The screenplay was written by Michael Winder; the director was Tom Clegg. The original title of the episode was "Devil's Moon". The final shooting script is dated 9 September 1976 and live-action filming began on Monday 1 November 1976 lasting through to Thursday 18 November 1976. The episode was first broadcast in the U.K. on 1 September 1977. Story 2306 days after leaving Earth orbit, the Moon is passing a solar system containing a pair of potentially habitable planets. John Koenig takes Eagle One on a reconnaissance flight with co-pilot Blake Maine. A sensor sweep of the larger world reveals a breathable atmosphere, vegetation, a city, but no life-signs except a single person. After landing, the two men follow the life reading, which ceases as abruptly as it appeared. They find a freestanding booth surrounded by dozens of corpses. Scanning the bodies suggests a neurological pathogen that the Alphans must be immune to. The investigation is interrupted when a shimmering light emanates from the booth. A man materialises and exits, then keels over and dies. Koenig and Maine depart. Flying over the city, they see corpses lying everywhere. Scans of the other planet reveal identical atmosphere and botanical life. While making a close pass, the Eagle blunders into a force-field. Koenig manages a quick mayday call to Alpha before they crash-land in a forest. They survive but then see a running man being hunted by a group of whip-wielding women. As the man tries to reach a sculptural column, the women corner him just short of his goal. When Koenig and Maine move to assist him, Maine runs into an invisible energy barrier and is vaporised, leaving just a smouldering uniform. Koenig is set upon by one of the women and clubbed unconscious with the hilt of her whip. This planet, Entra, is a prison for political dissidents sent from the other world, Ellna. The prison is run entirely by women and the inmates are all male. As the huntress-guards carry Koenig to their headquarters, a trial is underway there in a large hall. A prisoner stands accused of plotting an uprising against the ruling authority. Beside him stands Crael, a senior prisoner, pleading his case to Elizia, mistress-governor of this penal colony. But