The following contains spoilers for Star Trek: Picard Season 3, Episode 9, "Vox," now streaming on Paramount+.

Starfleet Admiral Elizabeth Shelby officially joined the ranks of Picard cameos in Season 3, Episode 9, "Vox." The fan-favorite character has appeared only a tiny handful of times in Star Trek canon, notably as a key part of the now-classic Star Trek: The Next Generation Season 3, Episode 26, "The Best of Both Worlds." Yet, despite that, she plays an extremely important part in the franchise's timeline, and her dynamic with the Next Generation crew -- particularly William Riker -- has never been duplicated.

Things don't go well for Shelby in "Vox," though the episode leaves her a bit of wiggle room for her to escape what appears to be an inevitable death. The irony comes in the fact that her appearance in Picard constitutes something of a final victory over Riker. Shelby -- an ambitious Starfleet officer -- ends up outranking the commander she once claimed was in her way.

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Shelby's Stint on The Next Generation Was Something Very Different

Star Trek The Next Generation Riker Picard and Shelby standing on the bridge in Best of Both Worlds

In The Next Generation, Shelby arrives on the Enterprise-D in "The Best of Both Worlds" holding the rank of lieutenant commander. She's billed as an expert on the Borg and comes to help the crew prepare some kind of defense against an imminent Borg attack on Earth. From the beginning, she and Riker are at loggerheads. Though he technically outranks her, she often takes action impulsively, and at one point, goes around him to speak to Captain Picard directly.

In the process, she becomes a fulcrum to address one of the show's thornier narrative problems. Riker is an exemplary Number One, and yet he never becomes a captain in his own right. Indeed, when Shelby arrives, Riker has been offered a captain's position on another ship. Everyone assumes he'll take it, and Shelby believes she'll be taking his position as Number One on the Enterprise. When he doesn't, she calls him on what she perceives as timidity. "If you can't make the big decisions, Commander," she tells him matter-of-factly, "I suggest you make room for someone who can."

Yet, far from a liability, Shelby's boldness provides a crucial component to the eventual defeat of The Borg in Season 4, Episode 1, "The Best of Both Worlds, Part II." Riker himself comes to respect her willingness to speak frankly and challenge his decisions if she feels he's wrong. When Picard succumbs to the Borg and becomes Locutus, he promotes Shelby to Number One upon taking command of the Enterprise-D, believing her to be the best choice over stalwart crew members like Data and Worf. Their dynamic worked so well that -- should the show have chosen to kill off Picard instead of saving him from The Borg -- it could have continued quite well with Riker as captain and Shelby as his new Number One.

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Picard Reveals That Shelby May Have Been Right About Riker

Admiral Elizabeth Shelby sits in a chair in Star Trek Picard

"Vox" finds Shelby holding the rank of admiral, and serving as the master of ceremonies for Starfleet's vaunted Frontier Day celebration. She's left unprepared for The Borg's sneak attack -- ironic considering her field of expertise -- and her final fate remains unknown as of this writing (though again, things look bleak). But her position confirms her initial assessment of Riker, at least to some extent. Having started as his subordinate, she now outranks him as an admiral to his mere captainship.

It's cold comfort considering the events of "Vox," but it also carries a finality that Shelby herself would doubtless relish. Riker begins Season 3 in semi-retirement, unlikely to rise above his current rank of captain. Shelby, on the other hand, is a mover and shaker in Starfleet. She even appears for Frontier Day at the helm of a freshly christened new version of the Enterprise, just to twist the knife. The big decisions, it seems, still go to the ones most willing to make them.

New episodes of Star Trek: Picard stream every Thursday on Paramount+.