Nutshell: Quite good. A few flaws, but an intriguing premise and a fresh way of utilizing a reliable Trekkian element.
I've always liked the Borg (but then again, who hasn't?). They're the most interesting and fearsome villains that Star Trek has ever come up with—not just because they're powerful and relentless, but because they're determined to force you to join them, quashing your free will and independent thought. As a result, I went into "Unity" with high expectations; and, for the most part, I came out quite satisfied.
First a digression: It's an interesting observation that Voyager as a series still hasn't come up with a fresh, new, defining "concept" for its Delta Quadrant milieu. TNG came up with the Borg in its second season, DS9 introduced the Dominion in its second season; but here we are in season three of Voyager—and I'm still not sure where the gold is (and apparently the writers don't either). Instead, in one of its better episodes to date, Voyager falls back on a reliable piece of TNG. I'm not condemning the creators for deciding to use old material—far from it. After all, as I said last week in my review of "Blood Fever," bringing the Borg to Voyager could potentially re-energize the series if they become a regular nemesis. Still, I find it an interesting and perhaps telling sign.
"Unity" isn't a rehashed Borg episode; it takes a completely new perspective on the Borg: the inverse perspective. Usually the Borg are automatons who seek to forcibly assimilate you into their Collective. But in "Unity," Chakotay and Ensign Kaplan (Susan Patterson) land a shuttle (it doesn't crash but it does later get disassembled and thus destroyed) on a planet of warring colonists who used to be Borg and have since been broken from the Collective. Kaplan is killed in an attack by a faction of colonists within minutes of the landing. (A show of hands—who didn't know the Ensign We've Never Seen Before would be killed in the course of the episode, or, more specifically, in the course of the first scene?)
Chakotay is shot and injured in this attack, but he's rescued by a group of colonists that includes a human named Riley (Lori Hallier) and a Romulan (Ivar Brogger), among other Alpha Quadrant humanoids. All these colonists were assimilated into the Borg Collective at one point, but an electrical storm severely damaged their cube five years ago, severing them from the Collective and returning the survivors to their original, individual selves. While Chakotay uncovers this realization on the planet, Janeway and the Voyager crew—out of contact with Chakotay—finds the mostly-abandoned Borg cube adrift in space.
The story takes the standard A/B-story structure but uses it effectively. The plots seem initially unconnected, but then come together plausibly and sensibly. The early scenes of Voyager's discovery of the Borg ship are creepy and ominous. Seeing a dead Borg ship is every bit as intimidating as seeing a live one, because there's the conceivable possibility that the dead ship will become a live one.
Upon boarding the ship and finding what's left of its crew is inactive for reasons unknown, the crew muses over what could've caused a Borg ship to "die." One of the best realizations in the episode is Torres' scarily amusing line: "Maybe the Borg were defeated... by an enemy even more powerful than they were." And Janeway's dry reaction: "Continue scanning for any Borg vessels in the vicinity—as well as any other ships that might be... 'more powerful'." It's the kind of comment that's long overdue in coming. After all, the Voyager is alone out here, and if they were to run into hostile Borg or someone "more powerful," they could have a big problem on their hands.
Chakotay's problem doesn't seem as initially threatening, but it's by far more complex and meaningful. Riley, along with her close Romulan ally, explains their intentions to Chakotay to form a new "Cooperative" to end the fighting on the settlement. Before revealing the nature of this Cooperative, however, Riley and her allies must help Chakotay, who will die of his injuries unless something can be done to stop his "neural degradation" (ah the Trekkian technical jargon, how I love it!). To heal his injuries, they must use a device to mentally connect him with several others in their group—absorbing him into a small, temporary type of Borg Collective to repair his neural damage.
Chakotay does not welcome such an idea, and it's easy to see why. As Riley says herself, it's understandable for one to be skeptical; but despite how fearsome and ruthless the Borg Collective can and has proven to be, there are great advantages to being interlinked with other minds—provided it's not put to destructive use.
This is the theme of "Unity" At what cost is unity a positive option? Chakotay experiences first-hand the sorts of advantages and pleasures being connected with other minds can bring: tenfolds of knowledge, efficient communication of ideas, not to mention a closeness to those in the link that far exceeds what one could ever find outside the Collective.
That brings us to Riley's New Cooperative. She wants Chakotay to help her bring peace to the colony by retrieving and reactivating the Borg cube and sending a signal from it that would give her the ability to unite the entire colony permanently, bringing unified peace and order to it.
That's a tall order. The repercussions are unpredictable and could be disastrous. Once Janeway locates Chakotay and the colony, Riley makes an official request to the captain, which, as one would expect, is not received with enthusiasm. The colonists may perhaps be well-meaning and sincere—as Chakotay can certainly attest—but it's not simply that easy, and Kenneth Biller's teleplay wisely knows that.
Reactivating one power generator on the Borg ship could reactivate the entire ship and the remaining Borg left on it. The consequences of that are obvious. Perhaps not as obvious, but more interesting, is the question of what exactly would become of the colony once it becomes a unified whole. "Unity" raises some implicit issues that are well worth close scrutiny.
For example, why are these people so willing to give up their individuality in favor of a New Cooperative? The whole message behind the Borg up to this point has been that assimilation into their Collective is worse than death itself—because one no longer has free will or independent thought over the power of the whole. When Riley and the other assimilated Borg were separated from the Collective five years ago, they were, to use Riley's own word, free—individuals with memories of their own pasts and identities. It's interesting—very interesting indeed—seeing that after the "euphoria" of freedom wore off and the fighting ensued, that Riley's best solution became to re-assimilate the colony into a new Collective which, without the Borg-inherent intention of being a group of conquerors, she comfortably labels the "New Cooperative."
It's therefore a subtle irony that when Chakotay informs the colonists that he can't help them they force him to help anyway, taking control of his actions by sending a signal to his shuttle and hijacking his thoughts. The action finale is punchy, as the crew races—and fails—to stop Chakotay from reactivating the Borg generator—which awakens the Borg drones and the vessel.
The New Cooperative sets the Borg's auto-destruct, however, perhaps as a sign of good will (leading to one of my favorite sights: a Borg cube getting blowed up real good!). Chakotay wonders however, how long the Cooperative's ideals will last in the face of such power. I wonder as well. The ideal of oneness and group cohesion frankly strikes me as quite dangerous. That's "Unity's" payoff, and why it works so well. It seriously asks what the difference is between the Borg and the New Cooperative. Is it inevitable that the Cooperative's power will lead them to seek out victims the way the Borg do? I think it's a distinct possibility. The fact that Riley's group activates this Cooperative without the consent of most of the colony is assimilation in and by itself; the motives begin to lose their relevance.
Detracting from the overall power of the show are a few small but noteworthy details that continue to plague the series' credibility. One is the destruction of yet another shuttle. These losses just can't be ignored week after week. Either the show has to acknowledge that the crew has found a way to build new shuttles or there should be great concern over losing them. Destroying a shuttle wasn't really necessary here anyway, so why did they do it? Ugh.
Then there's the aforementioned matter of the arbitrary killing of Kaplan—also unnecessary. And, of course, there's the excessive technobabble in the final "explanation" scene and the part where the severity of Chakotay's injury is revealed. Couldn't these passages have been written without uses of such convenient-sounding gobbledygook?
There's also a glaring logistic error: Riley explains she was originally assimilated during the battle at Wolf 359. How was that possible? That ship was destroyed in "The Best of Both Worlds, Part II" and had nothing to do with the cube that appears in this episode. This is only one line of dialog, and it's not a major demerit, but someone wasn't paying attention.
I don't want to sound like "Unity" was a negative viewing experience, because it wasn't. It's a standout episode. The special effects are as good as I've seen them on Voyager, McNeill's direction is effective, the story is fresh and implicitly complex, the production is impressive, and the action and suspense works. This is not the best episode of Voyager, but it's among them.