"The Troubled Spirit" is the nineteenth episode of the first season of Space: 1999. The screenplay was written by Johnny Byrne; the director was Ray Austin. The final shooting script is dated 11 November 1974. Live-action filming took place Wednesday 20 November 1974 through Wednesday 4 December 1974. Synopsis As the Moon drifts through empty space, the off-duty personnel of Moonbase Alpha gather in the Recreation Section for an evening of music. Playing to a full house, a solo artist performs a haunting piece on an electric sitar. At Hydroponic Unit Two Doctor Dan Mateo and three colleagues are in the midst of an unorthodox experiment. Linked to a transmitting apparatus by electrodes, the four botanists sit holding hands around a table, giving the proceedings the appearance of a scientific séance. Working from the premise that humans have an innate affinity with plants, Mateo has discovered that botanical life emits electrical waves analogous to those produced by the human brain. In the experiment, Mateo hopes to isolate these brainwave patterns in his own mind, amplify them using the combined mental powers of the group, transmit them at plants sitting on the table and measure the response. The ultimate goal is to establish communication between humans and plants. As the group concentrates, Mateo slips into a trance-state. Doctor James Warren, head of Hydroponics, enters the unit and stops the experiment. When the circle is broken, Mateo spasms in agony and crumples to the floor. Suddenly, the lights dim and a freezing wind blows all throughout Alpha. John Koenig arrives at Hydroponics with a medical team. Mateo is conveyed to Medical straight away while John questions the other participants. An argument breaks out between Warren and Laura Adams, Mateo's girlfriend and willing accomplice, as Warren repeatedly warned Mateo of the dangers while Laura is furious that Warren's interference could have cost Mateo his life. Their dispute is interrupted by a report that all of Alpha's sections experienced a momentary drop in temperature emanating outward from Hydroponics. Koenig presses Victor Bergman for an explanation, but the professor is stumped. In the Medical Centre, Mateo regains consciousness. After describing his experience to Helena Russell, she advises caution as he seems extremely sensitive to psychic phenomena. When Laura comes to check on him, the couple quarrel when she expresses her concerns over the dangers of continuing the experiment. Helena ends the spat by administering a