Ring Around the Moon (Space: 1999)

"Ring Around the Moon" is the twenty-first episode of the first season of the science fiction television series Space: 1999. It first aired on February 13, 1976.

Synopsis:

The episode centers on a mysterious phenomenon affecting Moonbase Alpha: a rapidly approaching ice ring is forming around the Moon, threatening to crush the base. Simultaneously, Commander Koenig and Professor Bergman begin experiencing strange occurrences: objects appearing and disappearing seemingly at random. They investigate, suspecting the presence of an alien intelligence.

It is eventually revealed that a powerful alien entity, a sentient planet named Retha, is responsible. Retha is projecting its memories and emotions onto Alpha, manifesting the objects and events Koenig and Bergman are witnessing. The ice ring is also a manifestation of Retha's power, representing a defensive mechanism.

The Alphans are able to communicate with Retha. They learn that Retha is lonely and desires companionship. By allowing Retha to share its experiences and connect with the Alphans, they persuade it to remove the ice ring and cease the disruptive manifestations, thereby saving Moonbase Alpha. The episode explores themes of loneliness, connection, and the potential for communication between vastly different forms of intelligence.