The Next Generation introduced the Borg right at the start of the series. They are made out to be at least one of the main villains of the show, through an encounter orchestrated by the near omnipotent Q. They continued to make appearances throughout Voyager, Deep Space 9, and even into more of the modern iterations into the franchise such as Picard. While never taking one specific form, with the occasional exception of the Queen, they act as the main nemesis for Picard himself. While their nature and powers have changed drastically since their first introduction, there remains one strange, yet creepy weakness present throughout their many appearances. They do not always respond to the presence of intruders aboard their ship.

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While this might sound fairly tame compared to all the other horrific and scary things the Borg do, it constantly makes for some of the most eerie scenes from the franchise. In several episodes, a Starfleet crew beams aboard only to be ignored by an array of mindless drones walking around like zombies. In the shows and movies, this peculiar behavior is used to create a sense of unease. But it also skillfully explores a leading Borg characteristic: they have such little regard for humans they don’t even see them as a threat.

The Borg see very little worth in humans due to their own, twisted Prime Directive. To them, the crew casually walking around their ship is comparable to a fly buzzing around a house. Most of the time, there’s no point in killing it, as it’s not really bothering anyone. The mysterious Borg were so powerful that they deemed it impossible that they could be harmed, even by people aboard their ship. So if they are not causing any havoc, then what’s the point in stopping them?

Scenes like these helped create an ominous feeling of dread for audiences. There’s a sense that, at any moment, these drones could realize that the people on board their ship were a threat and swarm their location, wiping them out without too much effort. The issue, however, was that the Borg never seemed to learn from their mistakes. More often than not, these seemingly irrelevant intruders aboard their ship were causing much more harm than they realized. On multiple occasions, these reconnaissance missions to a Borg cube led to the discovery of information or technology that could, and would, be used to defeat them. The plot point worked great for an eerie sense of dread, but never stood up to the scrutiny of logic.

The Borg’s lack of logical processing and adaptation meant that protagonists of the show did this multiple times. They gained unimpeded access to a Borg ship, rummaged around, and then used whatever they found to help destroy the seemingly invincible Borg. The Borg themselves never adapted to stop this. They only ever responded when the intruders showed physical ill intent, such as when they started shooting things or killing Borg. This is not just a one-off, either. In the episode “The Best of Both Worlds,” the crew of TNG boards a cube and install a virus aboard, destroying the ship. They again do something similar in “I, Borg” and “Descent Pt. 1 & 2.” They continue to let intruders walk around their ships all the way up until First Contact, the Frakes-directed movie that leans heavily on the creepy Borg element.

The Borg are some of the best, and simultaneously the worst, Star Trek villains. They had the potential to be great, and were for a while in the early TNG days. But for many fans, the additions to the Borg in the poorly reviewed Voyager and again in First Contact completely ruined the character of these villains. They made them a lot scarier and more visceral, but they seriously debuffed them. Thus, they became much easier to defeat even by the fairly weak (in comparison) yet still iconic USS Voyager. Writers perhaps leaned too heavily on the effective creepy element of intruder non-interference. In doing so, they accidentally opened up a plethora of Borg weaknesses and undermined their destructive power.

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