Warning: SPOILERS for Star Trek: Picard Season 1, Episode 5

Seven of Nine (Jeri Ryan) has joined Star Trek: Picard, but her activities in the years since Star Trek: Voyager ended are disappointing. Trekkers were shocked and thrilled when it was revealed that Seven would be part of Patrick Stewart's revival series about Jean-Luc Picard's twilight years. Seven is a beloved fan-favorite hero who had never interacted with any characters from the other Star Trek series so a team-up between Seven of Nine and Picard, who was once Locutus of Borg, is certainly a Star Trek fan's dream come true.

Seven of Nine joined Star Trek: Voyager in the "Scorpion" two-parter that bridged seasons 3 and 4, and she quickly became so popular, Seven supplanted Captain Kathryn Janeway (Kate Mulgrew) as the face of the series. A reclaimed Borg who was assimilated when she was a child named Annika Hansen, Seven of Nine brought an air of danger to the starship as she butted heads with its Starfleet crew, especially Janeway. And, for fans (especially males), Seven in her skintight metallic catsuits brought an undeniable sex appeal to Voyager as well. With Seven aboard, Star Trek: Voyager integrated the Borg into the series since the starship was lost in the Delta Quadrant, the region of the galaxy the cyborg race originated from. Seven eventually bonded with the crew and sparked a romance with First Officer Chakotay (Robert Beltran); she returned to Earth with Janeway's vessel in Star Trek: Voyager's series finale, "Endgame", which was also the last time Seven of Nine was seen in Star Trek canon.

Related: Star Trek: Picard (Wisely) Avoided An Admiral Janeway Cameo

In Star Trek: Picard episode 4, "Absolute Candor", Seven staged a surprise rescue of Picard and beamed aboard his new ship, La Sirena, but fans didn't learn what she's been up to after Voyager ended until episode 5, "Stardust City Rag": In the years after the Romulan supernova, Seven of Nine left Earth to join the Fenris Rangers, which is a vigilante group that patrols Romulan space helping people in need. Picard (and Starfleet) frowns on the Rangers for their "lawlessness" and for styling themselves as "judge, jury, and executioner", but as Seven explained her side of things, after Picard quit Starfleet and "gave up" when the Federation turned their backs on evacuating the Romulans, the Neutral Zone collapsed and the Beta Quadrant plunged into chaos. The Romulan Star Empire was no more and the Rangers, based from the planet Fenris, took it upon themselves to help keep the peace from the Romulan warlords who were springing up in the star system.

Star Trek Seven of Nine And Picard

On one hand, it's noble that Seven of Nine became a galactic sheriff and action hero who helps the helpless, although it led to tragedy. In 2386, soon after becoming a Fenris Ranger under her human name, Annika was tricked by a crime lord named Bjayzl (Necar Zadegan), who wanted to harvest her Borg implants. Bjayzl kidnapped Icheb (Casey King), Seven's surrogate son who was also a reclaimed Borg introduced in Star Trek: Voyager, and violently stole his tech. Seven killed Icheb out of mercy and swore revenge on Bjayzl, which she finally exacted in "Stardust City Rag" by disintegrating the criminal with phaser rifles at point-blank range. However, it's disappointing that Seven of Nine's life was plunged into violence and pain in the decades after Voyager returned to Earth, to the point where she became a stone-cold killer.

Star Trek: Picard offered no hint of what became of Seven's relationship with Chakotay, besides the fact that it's obviously long over. It's also sad that Seven, who still struggles with affirming her lost humanity, didn't stay in Starfleet with her friends from Voyager nor did she find any happiness living on Earth. However, Seven may have been forced to leave the Federation after artificial lifeforms were banned since much of her body still harbors Borg implants. So, Seven returned to space with the intention to help those in need after the Romulan supernova but she settled into the "hopeless, pointless, and exhausting" life of a vigilante, in Seven's own words. Trekkers had higher hopes for Seven of Nine so it's crushing to see the tragic turn her life has taken. However, Seven did offer Picard a way to contact her if he needs her help so, if and when Seven of Nine does return to Star Trek: Picard, hopefully, she'll spill some of the details about what became of Voyager's crew that fans are dying to know.

Next: Star Trek: Picard's Voyager Tech Proves Starfleet's Hypocrisy 

Star Trek: Picard streams Thursdays on CBS All-Access and Fridays internationally on Amazon Prime Video.