It's the first time we see what would become the most prolific and unique antagonists in 'Star Trek'; The Borg. Designed to usurp the unimpressive (at the time) Ferengi as the primary threat for The Federation, this cybernetic menace broke into the zeitgeist with a mightily impressive debut. They're unstoppable; a far cry from what they would become.
This is a look at Q-Who, a confident, definitive episode of TNG that would have decades long consequences.
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