Stories related to her relationship with Captain Janeway and with The Doctor appeared throughout the series; some episodes, such as "The Raven", explored her background and earlier life as Annika Hansen before she was assimilated by the Borg.

Following the third season of Star Trek: Voyager, the production team decided that the main cast character of Kes was to be dropped from the show.

In addition, the producers of Voyager had been keen to make greater use of The Borg as recurring antagonists in the show, particularly after the success of the 1996 Next Generation feature film Star Trek: First Contact.

[6] In the following years, the Voyager writers wrote several plot lines revolving around Seven's exploration of the positive and negative sides of human individuality.

After the addition of the former Borg drone to the starship's crew at the start of the fourth season of Voyager, the shows' weekly viewer ratings increased by more than 60%.

[16][17] As the end of the series approached, Ryan remarked that she would "love to do something without special effects or rubber glued to my face, it'd be a nice change of pace.

"[19] Ryan said that she had several favourite Seven of Nine episodes, including "The Gift", "The Raven", "Revulsion", "Hunters", "Prey" and the two-part "The Killing Game".

[28] At the age of four, her parents were given use of the research vessel USS Raven by Starfleet to help them investigate the presence of an unknown species in deep space.

[30] Following this, she was a Borg drone and assimilated individuals from a number of species, including a crew member from the USS Melbourne at the Battle of Wolf 359 on Stardate 43989.1.

Janeway is injured, leaving Chakotay in command—but he distrusts Seven and the Borg and after he refuses to work with her, she sends the vessel into fluidic space to force them to develop the weapon.

[28] Seven immediately comes into conflict with Chief Engineer B'Elanna Torres in "Day of Honor" and puts Voyager in danger when the Caatati steal the warp drive and hold it hostage for supplies and Seven herself.

Instead, she builds a thorium generator to power their vessel, which the Caatati accept in exchange for the core and for allowing the rescue of Torres and Lt. Tom Paris.

[29] After some time, Seven begins to question why Captain Janeway continues to make contact with alien species as they travel back to Earth, as it often results in incidents.

In response, the Captain punishes her by restricting her computer access and confines her to the cargo bay where her Borg regeneration unit is set up.

[39] During the events of "The Killing Game" where the Hirogen take over Voyager and place the crew in the holodeck for hunting practice, Seven is brainwashed into thinking she was a French club singer during the Nazi occupation of France.

Using a Borg temporal transmitter, Chakotay and Harry Kim manage to send information back in time to Seven to prevent the destruction of the ship.

[47] She becomes involved in a time-travel plot once more when Captain Braxton of the Federation timeship USS "Relativity" pulls her out of the timestream to help prevent the destruction of Voyager.

In Picard, set more than twenty years after the finale of Voyager, Seven is a member of the Fenris Rangers, a peacekeeping organization active near the former Romulan Neutral Zone.

[50] Ryan notes her portrayal is "much more human" and developed a new speaking cadence to reflect the character's two decades living in Federation space.

She and Picard discuss their mutual difficulty regaining their humanity after being assimilated by the Borg, and she disembarks under the pretense of rejoining the Rangers, but actually transports back to the surface and vaporizes Bjayzl.

In the final episode of Star Trek: Picard, Tuvok promotes Seven of Nine to the rank of captain, revealing that Shaw had given her a glowing recommendation for command in spite of the friction between them.

The game is set beyond the end of the original Voyager series, with the storyline placing Seven on board the USS Callisto as a science advisor to the Federation fleet which is returning to the Delta Quadrant.

"[22] The initial fan reaction was mixed with some accusing the show of adding her to attract more 18–35 male audience members, which was denied by Braga.

[20] The character's attire, numerous form-fitting catsuits with distinct rib-lines and a high stiff neck, was criticized by veteran Star Trek writer/producer Ronald D. Moore, who felt she should have a more Borg-like appearance.

[63] Her outfit also annoyed some who felt that it was an attempt by the show's creators to make her sexually appealing to some viewers, without any storyline purposes intended.

[64] Keith DeCandido of Tor.com was critical of the hair and costume which "for reasons that have absolutely nothing to do with the character and everything to do with external factors" but that Ryan's performance manages to elevate matters, and give Seven a compelling journey.

[66] Ziauddin Sardar said in the New Statesman that her appearance on Voyager "restored the warp drive" to the show,[67] resulting in a "triumphant note" to the start of the following season.

"[12] Rob Owen at the Chicago Sun-Times said that the majority of the Voyager cast were "lacking in depth" with the exception of Seven, the Doctor and Captain Janeway.

[68] By the end of the series, Seven was described as the "most bewitching cast member" and the "first authentic Trek bombshell since Uhura" by Frank Ahrens at The Washington Post.

[83] Seven was received as one of the Voyager characters who filled a Spock-like role,[84] alongside Tuvok,[85] with her "blonde bombshell" appearance balanced by "intelligence, boldness, rationality and a remarkable lack of interest in the opposite sex".