Kes is a fictional character played by Jennifer Lien on the American science-fiction television show Star Trek: Voyager. The series follows the crew of the starship USS Voyager, stranded far from home and struggling to get back to Earth. Kes joins the crew in the pilot episode "Caretaker", opening an aeroponics garden and working as the medical assistant to the artificial intelligence known as the Doctor. She is a member of a telepathic alien species known as the Ocampa, who have latent psychic abilities and a lifespan of only nine years. Her storylines focus on encouraging the Doctor to develop his humanity and dealing with her Talaxian boyfriend Neelix's jealousy. She also seeks to expand upon her mental capabilities, leaving in the fourth season after her powers threaten to destroy the ship. She reappears in a season-six episode and features in Star Trek: Voyager novels and short stories.

Voyagers creators Rick Berman, Michael Piller, and Jeri Taylor designed Kes to be a rapidly aging character who would provide audiences with a different perspective on time. Although Kes is portrayed as fragile and innocent, she is also shown as having hidden strength and maturity. Voyagers producers reluctantly fired Lien after her personal issues affected her reliability on set. At the time, this was not openly discussed, and her departure was attributed to other reasons; these ranged from Lien voluntarily leaving to pursue other roles to her being removed to make room for Jeri Ryan's introduction as Seven of Nine.

Kes was a fan-favorite character while Voyager was airing, although critics reacted more negatively, finding the character boring and without a clear purpose. Lien was praised for her performance, which was highlighted in reviews of individual episodes. Kes's age was the subject of critical discussion, questioning if she was too young to be dating Neelix. Lien's removal from Voyager received mixed reviews from critics; some preferred the addition of Seven of Nine, while others were disappointed by this casting change. Reviewers and fans disliked her return in the season-six episode "Fury", which some media outlets called one of the worst moments in the Star Trek franchise. Academics have analyzed Kes's representation of femininity, her relationship with Captain Kathryn Janeway, and her mental abilities.

Appearances Background and introduction Introduced in Star Trek: Voyagers pilot episode "Caretaker", Kes is an Ocampa—a telepathic alien species with latent psychic abilities and a lifespan of nine years. She was born and raised on the Ocampa home world in an underground city, which was constructed by an alien known as the Caretaker after he inadvertently destroyed the planet's atmosphere. The Ocampa have grown dependent on his care. The Caretaker realizes he is dying and abducts beings from across the galaxy, including the Starfleet crew of the starship USS Voyager. He does this to find a compatible mate to produce an offspring who would continue caring for the Ocampa.

Kes dreams of exploring the galaxy and finds a way out of the city, but is captured and tortured by the Kazon. She is rescued by her Talaxian boyfriend Neelix who is assisted by Voyager captain Kathryn Janeway and her crew. When the Kazon attack and attempt to steal the Caretaker's technology, Janeway orders the destruction of his vessel. Stranded in the Delta Quadrant, she agrees to have Kes and Neelix remain on Voyager.

On Star Trek: Voyager Aboard Voyager, Kes starts an aeroponics garden to provide produce to the crew. While working as a medical assistant for the Doctor, an artificial intelligence projected as a hologram, she encourages him to develop his social skills and the crew to recognize him as more than a machine. The Vidiians harvest Neelix's lungs in "Phage", and Kes donates one of her own to him. In "Elogium", emanations from space-dwelling lifeforms cause Kes to prematurely enter a fertile period. An Ocampa goes through this process only once and it is her only time to have a child. After discussions, Neelix agrees to be a father, but Kes decides against having a child. When Voyager moves away from the aliens, the Doctor determines Kes had a false alarm and would be able to conceive in the future. Neelix grows more paranoid regarding Voyagers helmsman Tom Paris and his interest in Kes, such as in "Twisted"; the two resolve this tension in "Parturition" during an away mission.

When Voyager discovers an Ocampa colony in "Cold Fire", its leader Tanis teaches Kes psychokinesis. Prior to this, Security Chief Tuvok had been training Kes. She uses her abilities in earlier episodes, including having visions of a planet's destruction in "Time and Again" and showing an eidetic memory in "Eye of the Needle". Unable to control her psychokinesis abilities, she destroys the aeroponics garden and nearly kills Tuvok by boiling his blood. The crew discovers that Tanis is working with the Caretaker's mate, Suspiria, to destroy Voyager, but Kes subdues him with her powers. In "Warlord", Tiernan, a former dictator of the planet Illari, possesses Kes and uses her abilities to stage a coup on the new leader. Under his influence, Kes breaks up with Neelix. Although Voyager frees Kes from Tieran's control and kills him, the experience traumatizes her.

In "Darkling", Kes is attracted to Zahir, a member of an alien species of explorers, and considers temporarily joining his journey. The Doctor injures Zahir and kidnaps Kes after developing an evil alter ego while grafting new personalities into his program. After the Doctor is returned to normal, Kes decides to remain on Voyager. Throughout "Before and After", Kes lives short periods of her life in reverse order, from her death to her conception, as part of an alternative timeline. During "Scorpion", Kes becomes telepathically connected with Species 8472, who are at war with the Borg.

Kes's powers advance at an exponential rate in "The Gift" to the point that she can no longer stay aboard Voyager, as they threaten to destroy the ship. Leaving on a shuttlecraft, she hurls Voyager and its crew safely beyond Borg space, roughly 10,000 light-years closer to Earth, before turning into living energy. In "Fury", Kes is unable to control her evolving mental abilities, and she fears that she would not be accepted by other Ocampa. She blames these changes on Janeway for allowing her to join Voyager. Breaking into Voyager, she travels back in time to negotiate with the Vidiians to take her younger self back to the Ocampa home world. The younger Kes makes a hologram to remind her future self about her love for the crew. This message encourages the older Kes to return to Ocampa.

Other appearances In 1995, Pocket Books began publishing Star Trek: Voyager novels set during the show's run and after its series finale. Kes appears in the 1995 novelization of "Caretaker" by L. A. Graf and the 1996 book for "Flashback" by Diane Carey. Nathan Archer began writing the 1995 book Ragnorak, before the pilot episode aired and said that his interpretation of Kes, based on the series bible, was radically different from her depiction in the show. In Greg Cox's 1997 novel, The Black Shore, Kes has horrific visions after the crew takes shore leave on a seemingly idyllic planet. Cox included scenes between Kes and Chief Engineer B'Elanna Torres after reading an interview in which actor Roxann Dawson, who portrays Torres, talked about how the characters rarely interacted. Marooned, published in the same year, focuses on Kes being kidnapped by a space pirate; the author Christie Golden said that she wanted to explore how Kes would appear to an alien with a lifespan of thousands of years.

Kes appears in stories published after Voyager ended. She goes back in time to help create an Ocampa and Nacene hybrid in the String Theory trilogy (2005–2006) by Jeffrey Lang, Kirsten Beyer, and Heather Jarman. The book describes the Kes from "Fury" as the "manifestation of her dark side" made as a byproduct of this time travel. Jarman used Evolution to explore questions she had with Voyager, such as how Neelix felt about Kes after her departure and what the Ocampa home world looked like in the past. In Beyer's 2012 book, The Eternal Tide, Kes helps to resurrect a dead Janeway.

Kes is also depicted in short stories, like Penny A. Proctor's "Restoration" from the 2002 anthology Star Trek: Strange New Worlds V in which she revives Ocampa's ecosystem. She is included in three stories from the 2005 collection Distant Shores. In Kim Sheard's "Winds of Change", Kes struggles with aggression after "Warlord" and asks Torres for advice. Sheard developed the concept after being told the anthology would focus on unusual character combinations. "Closure" is about Neelix seeing Kes after being caught in a cave-in with former Borg drone Seven of Nine. The author James Swallow was inspired by how Ethan Phillips, who plays Neelix, wanted closure for his character's relationship with Kes. In "Brief Candle", Neelix talks about one of his memories with Kes; the writer Christopher L. Bennett said she was one of his favorite Voyager characters.

Development Creation and casting Kes was one of the first nine characters that Star Trek: Voyager creators Rick Berman, Michael Piller, and Jeri Taylor developed for the crew of the USS Voyager starship. Inspired by the Star Trek: The Next Generation episode "The Child", Berman, Piller, and Taylor wanted to feature a rapidly-aging character to encourage viewers to reflect on time. Early in production, they nicknamed Kes the Mayfly to reference her short lifespan. She was set to age a year at the midpoint of each season to emphasize this rapid age progression.

In initial descriptions, Kes was characterized as a potential scout and expert on gangs, but was later changed to be a medical intern, while Neelix assumed a similar role as a guide. When Berman, Piller, and Taylor wrote Kes with psychic powers, production assistant Zayra Cabot hired a paranormal-focused consulting firm, Joan Pearce Research Associates. Joan Pearce created a list of psi abilities, which was used to decide that Kes would be shown with limited telepathy in the pilot episode ("Caretaker") with further exploration of her power planned for later episodes.

Early in Voyagers development, it was undetermined if Kes would be female, male, or androgynous. "Caretaker" director Winrich Kolbe wanted an actress who "could be fragile but with a steely will underneath". Jennifer Lien was an "early selection" for the role; Taylor said that she had "this wonderful elfin quality" and projected vulnerability and strength in her audition. Lien was unfamiliar with the Star Trek franchise, and at the age of 19, she was the youngest actor on the show. Jennifer Gatti had also been considered for the role, and would later guest star in the episode "Non Sequitur".

For the pilot, Robert Blackman designed Kes's wardrobe and Michael Westmore created her prosthetic ears. Blackman had difficulty dressing Lien as Voyagers producers were unclear on her character's direction. His initial design was for a pastel-colored costume inspired by a sprite; producers rejected it, instead suggesting a costume similar to Peter Pan's. The final look was partially modeled on Joan of Arc. Kes's wardrobe primarily consisted of tunics, and Lien wore a short blonde wig. Lien tested combinations of wigs and prosthetics, which cinematographer Marvin V. Rush filmed for Berman's final approval. Westmore kept the prosthetic simple to facilitate working on 30 Ocampa characters for the pilot episode. Lien said the ear prosthetics impaired her hearing, and she developed an allergic response to them as the series progressed. Starting with the episode "Before and After", Lien no longer wore the prosthetics and used her longer hair to cover her ears and hide this change; around this point, her costumes also transitioned to tighter jumpsuits.