At the beginning of the episode, Geordi La Forge, Commander Data, and Beverly Crusher are testing an interface which allows La Forge to use the VISOR-compatible circuitry in his brain, along with a virtual reality suit, to control a probe by remote control. This way La Forge can use the probe to go into areas that would be too dangerous for crew members to enter.
Geordi uses the interface to the probe to look for survivors on a ship that is trapped in a gas giant's atmosphere. He finds that there is no one left alive on the ship, but believes that he encountered his mother on the ship. Continued use of the probe soon exposes La Forge to unhealthy levels of neural stimulation. At about the same time Captain Picard learns that the ship that La Forge's mother commanded had disappeared.
La Forge is convinced that his mother was on board the ship, and wants to use the probe to communicate with his mother. But Crusher and Picard refuse to allow him to use the interface suit again. La Forge decides to use the suit anyway. While in contact with the probe, he encounters the being who appears to be his mother again, but learns that she is actually a lifeform native to the gas giant. This being talks La Forge into taking the ship closer to the planet, so that she and others like her trapped on the ship can go home.
In the end, La Forge realizes that his mother is in fact dead, and that it had all seemed so real he had thought he had a chance to say goodbye to her.