"The Lights of Zetar" is a third season episode of the original science fiction television series, Star Trek, first broadcast on January 31, 1969, and repeated on August 26, 1969. It is episode #73, production #73, written by Jeremy Tarcher and his wife Shari Lewis (who was best known as a children's entertainer), and directed by Herb Kenwith.

In this episode, strange incorporeal aliens threaten the Memory Alpha station and the Enterprise.

On stardate 5725.3, the Federation starship Enterprise heads for Memory Alpha, a planetoid where the Federation has set up a storehouse of computer databases containing all cultural history and scientific data it has acquired. While en route, the ship detects a strange energy storm moving at warp factor 2.6 and on a course to the planetoid. Given the storm's faster-than-light speed, it is believed that it cannot be a natural phenomenon.

The Enterprise intercepts the storm which bypasses the ship's shields and penetrates the hull. The exposure to the storm begins to affect crew members' nervous systems differently; Communications Officer Lt. Uhura is unable to move her hands, Navigator Ens. Chekov is unable to control his eyes, and both Captain Kirk and Helmsman Lt. Sulu are unable to speak.

Lieutenant Mira Romaine, aboard to oversee the transmission of newly acquired data from the Enterprise to the Memory Alpha station, faints from the effects of the storm, much to Chief Engineer Scott's dismay, as he's starting to fall madly in love with her. Chief Medical Officer Dr. McCoy examines Mira who seems paralyzed and unresponsive and makes strange grunting sounds as she lies on the deck of the bridge. Mira soon recovers in sickbay and refuses to be examined any further.

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