The crew tries to prevent the destruction of Earth.
The crew continues to fight Starling, who has made a deal that threatens the entire timeline, while Janeway and Chakotay try to find a way to stop the disaster before it occurs. The time-travel plot comes to a head, and the stakes grow.
The story concludes with the crew working to repair the timeline, and it includes the introduction of the Doctor's mobile emitter, a piece of future technology which allows him to leave sickbay. This was one of the most significant changes for the character, and it affects stories for the rest of the series.