When Kes undergoes chroniton particle treatment in a bio-temporal chamber to extend her lifespan, her cells are left in a state of flux causing her to be out of temporal sync. She then travels back and forth through time, experiences the beginning and final phases of her Ocampan lifespan and gets a glimpse of the Voyager crew's future.

Jessica Collins (Linnis Paris-Kim)
Garrett Wang (Ensign Harry Kim)
Michail L. Maguire (Arnis)
Christopher Aguilar (Andrew Kim)
Janna Michaels (Young Kes)
Rachel Harris (Martis)

• In the future that Kes experiences, the crew is attacked by a race known as the Krenim. The Krenim use chronoton torpedoes which interact with the bio-temporal chamber to cause Kes to go out of temporal sync. The crew refer to the time passing through Krenim space as the "Year of Hell." In this future, Janeway, Torres and Joe Carey are killed by the Krenim. Chakotay assumes Captain. Paris and Kes eventually marry and have a child, Linnis, who also ages at the same rate as Kes. Linnis marries Harry Kim and they have a child, Andrew, who also ages quickly. In addition to Chakotay, Tuvok, Paris, and Kim have all been promoted; Neelix wears a Starfleet uniform and is a security officer.
  
• When Kes returns to present time, she warns Captain Janeway about the Krenim. Voyager will encounter them in the Season 4 two-part episode "The Year of Hell".
  
• The future Kes had long, curly hair. When she returns to the "present," she still has long hair, which she keeps the rest of the season.
  
• The events of this episode will contribute to Kes' departure in Season 4.