"The Dorcons" is the twenty-fourth episode of the second season of Space: 1999 (and the forty-eighth and final overall episode of the programme). The screenplay was written by Johnny Byrne; the director was Tom Clegg. Original titles were "Last of the Psychons" and "Return of the Dorcons". The final shooting script is dated 17 November 1976. Live-action filming took place Tuesday 7 December 1976 through Thursday 23 December 1976. Story It is 2,409 days after leaving Earth orbit, and Moonbase Alpha is tracking an unidentified powered object following the Moon. Sensors detect no life forms and the craft is emitting an energy field highly sensitive to matter. The Alphans conclude the object to be a robot survey device. The object continues to close, the energy field making contact with the Moon surface. The instruments suddenly register a tremendous energy surge. As John Koenig orders defensive measures, the object projects a ray at Alpha that not only penetrates the defence screens but underground into Command Centre. As the light-beam appears in the room, all personnel are immobilised, with the exception of Maya. The ray's first action is to short-out the Main Computer input terminal. It then roams the room, briefly pausing on each person's face. When it encounters Maya, it focuses on her and the Psychon woman experiences horrible pain. With an agonised shriek, she collapses. Its goal achieved, the light disappears and the others are released from their paralysis. As attempts to contact the inert survey device fail, technicians examining Computer discover damage to its data-bank. Helena Russell tends to the unconscious Maya; her preliminary diagnosis is shock due to neurological trauma. To everyone's relief, Maya soon comes to. She tells them the ray was a mind-probe; after singling her out, it intensified and almost tore her mind apart. Concerned, Koenig questions the doctor about the possibility of brain damage. Sensors detect activity from the alien object—it is losing molecular cohesion, transforming into a gaseous mass of raw matter. As they watch, the mass expands and solidifies, becoming an impressive spacecraft. Maya is terrified at the sight of it, sobbing that the light was a Dorcon probe and that the ship is after her. She explains the Dorcons are the most powerful race in this galaxy and her people's most feared enemy. A scan of the vessel reveals a meson converter, a power system that can convert matter to energy,