Lt. Barclay hides in holodeck fantasies about the crew.
Lieutenant Reginald Barclay, a shy and awkward engineer, has trouble fitting in on the Enterprise. To cope, he escapes into the holodeck, where he plays out fantasies in which the senior officers appear as exaggerated versions of themselves. When his crewmates discover the programs, he is embarrassed, but the ship also faces a technical crisis.
The episode is a gentle story about loneliness and escapism, and it shows that the ship is a community of real people with real insecurities. Barclay became a popular recurring character, appearing in later episodes and in a later series. The story is also an early example of a theme about people's attachment to virtual worlds that feels very modern today.