Star Trek: The Next Generation has often been described as “groundbreaking.” Groundbreaking in what way, you may ask? Here are ten episodes that might, for one reason or another, be described as “groundbreaking”…

“Groundbreaking,” it should be noted, does not mean “first.” None of the tropes, themes, plot devices or issues discussed here appeared first on Star Trek; all had been explored before in different ways, often in different media, sometimes in differently formatted television shows (usually Doctor Who).

But it was Star Trek: The Next Generation that showed that these things could be done within the framework of series television, and within the sometimes conservative world of Star Trek.

“Groundbreaking” also does not mean “good.” Some of the episodes listed here are not, in fact, what you’d call “good,” and could even be described as “bad.” But they are trendsetters, risk-takers, or experiments, without which Star Trek as we now know it — and perhaps genre television as we now know it — would not exist.