Who is Jeri Ryan's Seven of Nine, one of several returning characters in Star Trek: Picard? Prior to this year's San Diego Comic Con event, very little was known about Patrick Stewart's Star Trek: Picard solo series, other than that the titular Starfleet legend would be retired at the outset of the story. Many Star Trek fans were anticipating that Picard may rendezvous with some of his pals from The Next Generation in this new adventure, but the connectivity to previous series actually runs far deeper.

In an action-packed trailer, Picard stumbles across the familiar form of Seven of Nine, once again portrayed by Jeri Ryan. This particular reveal caught everyone by surprise, as the character was a mainstay of Star Trek: Voyager, rather than Picard's own The Next Generation. Nevertheless, Ryan's return was met with an overwhelmingly positive reaction from the franchise faithful, and speculation soon followed as to what the future may hold for this popular Star Trek character.

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With Seven of Nine returning to screens once again, it's perhaps worth looking back at her Star Trek origins, her time aboard the good ship Voyager, and the future continuation of her story in Star Trek: Picard.

Seven Of Nine's Star Trek Origins

Jeri Ryan as Seven of Nine and Robert Beltran as Chakotay in Star Trek Voyager

Star Trek: The Next Generation introduced a brand new race of formidable villains, the Borg - a cybernetic breed of hive-mind life forms determined to remake every other living creature in their own image via the process of assimilation. Despite their violent intent, the story of Hugh established that Borg could be reformed. By separating them from the Collective and reprogramming their functions, a Borg drone could develop autonomy and mental freedom. This concept was developed further with Seven of Nine in Star Trek: Voyager.

Seven of Nine was born as a human named Annika Hansen on the Tendara Earth colony. Both of Annika's parents were Federation scientists tasked with studying the existence and biology of the Borg race and, unsurprisingly, this hazardous occupation would ultimately lead to the Hansen family's demise. As their studies became more detailed, the Hansens set out for Borg territory with a 4-year old Annika in tow, following one of the infamous Borg Cubes into the Delta Quadrant. Thanks to their scientific ingenuity, the Hansens remained undetected for two years, walking anonymously among the Borg. However, an ion storm rendered their ship's purpose-built shields useless for several seconds - more than enough time for the Borg to notice their presence and swoop in.

Annika spent almost two decades as a part of the Borg Collective under the designation Seven of Nine, Tertiary Adjunct of Unimatrix 01.

Seven Of Nine In Star Trek: Voyager

Jeri Ryan as Seven of Nine in Star Trek Voyager

Facing the might of a new threat known only as Species 8472, the Borg were forced into an uneasy alliance with the Voyager crew, with Janeway offering the Collective new weapons in exchange for safe passage in Star Trek: Voyager's season 3 finale. The Borg sent Seven of Nine onto the Federation vessel as their representative and, as one might expect, the Borg tried to break their end of the bargain once they got what they desired. Captain Janeway did indeed expect this betrayal, and as Seven of Nine moved to assimilate the crew, Lieutenant Torres overloaded the Borg implant in Annika's body, destroying her connection to the rest of the Collective.

The Voyager's holographic doctor reverted Seven of Nine's physical form back to that of a human, as far as was possible, but some Borg trademarks remained, including the machine-like thought processes and a struggle to identify as human. In season 4's "The Raven," the Voyager visited the site of the crashed Hansen family ship, and Seven regained her memory of the assimilation she suffered as a child.

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From this point, Seven's gradual transition from Borg to human becomes one of Star Trek: Voyager's central themes. Professionally, the new crew member uses her technological expertise to assist Voyager in the role of a science officer, facilitating numerous upgrades on board the ship. Personally, however, Seven's new life proved far trickier. Over the remaining 4 seasons, Seven became increasingly more human and independent in nature, despite several moral clashes with Captain Janeway and others. One of Seven of Nine's most memorable moments came in season 5's "Drone." Using the traditional "transporter malfunction" explanation, Seven found herself with a clone child, allowing the former Borg to explore her new-found maternal instincts. The artificially-created drone realizes his presence puts Voyager in danger and duly sacrifices himself, giving Seven of Nine a profound sense of loss for the first time since her assimilation.

Eventually, of course, Seven becomes a close friend of Janeway's and a trusted member of the Voyager crew. She even develops romantic associations with various characters, although some might argue the sexual element of Seven of Nine was played upon heavily.

Seven Of Nine In Star Trek: Picard

Seven of Nine in Star Trek: Picard

Not a great deal is known about Seven of Nine's role in Star Trek: Picard, but it can be gleaned from the trailer that she'll likely be helping Picard somehow on his mission to protect a mysterious young girl from harm. Seven's return is surely also connected to the wider Borg presence in Star Trek: Picard. The footage released thus far reveals a Borg Cube and a Romulan facility that seemingly keeps Borg captive. It's surely also no coincidence that Star Trek: Picard brings together Seven of Nine and her spiritual predecessor, Hugh. Both of these characters explored the same themes of individuality and second chances and those concepts could also form the heart of Star Trek: Picard.

Jeri Ryan's brief appearance in the Star Trek: Picard trailer also implies that her and the former Enterprise captain meet away from Earth, perhaps after Stewart's character has set out with his new crew. Interestingly, Seven of Nine's speech patterns in Star Trek: Picard are far less formal than her days on the Voyager, suggesting some significant progression for the character. Seven seems cynical about Picard coming out of retirement, and the scene's homely setting suggests that the former Borg may have left Starfleet and settled down herself after arriving from the Delta Quadrant. It remains to be seen whether Star Trek: Voyager's Chakotay will appear, since the First Officer and Seven married in one future timeline.

Seven of Nine isn't set to be a member of Star Trek: Picard's main cast, but more of a fan-pleasing guest star. Nevertheless, her return allows the Star Trek franchise to give fans an insight into Seven's continued human development, whether she lived a full and happy life and possibly even the fates of other Voyager crew members.

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Star Trek: Picard premieres in early 2020 on CBS All Access and Amazon Prime.