Plot summary
The Delta Flyer commanded by Harry Kim is caught in the crossfire between Kraylor and Annari ships. The Kraylor claim to be on a humanitarian mission; the Flyer protects the Kraylor vessel and the Annari retreat.
The Kraylor command crew is dead, and Kim assumes command to help complete their vaccine delivery. Kim names the ship Nightingale after the famous wartime nurse. With Seven's help Kim learns to be a better Captain. During an emergency, the ship's doctor Loken is unable to treat injuries but provides instructions for their cloaking device; he reveals they are not doctors carrying vaccines but instead scientists researching cloaking technology to penetrate an Annari blockade. Despite the deception, Kim feels responsible for the crew as Captain. At the Annari blockade, the Nightingale is held by a tractor beam but under Kim's command they break free and reach the planet. Kim and Seven return to Voyager, with Kim accepting that he still has a lot to learn before he can take command.
Credits
Adapted from Wikipedia contributors, Nightingale (Star Trek: Voyager). Paragraphs and formatting adjusted; illustrations, reference markers, block quotations and non-story material omitted.