In early Star Trek: The Next Generation episodes, the Borg appeared as a faceless hive mind with no single leader. When the film Star Trek: First Contact came out in 1996, the writers introduced the Borg Queen to give the story a central, recognizable villain. They believed audiences would respond better to a tangible antagonist than to an entirely leaderless collective, so the Queen became the voice and face of the Borg on screen.
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