With a twist... Literally!
Nor did we see that coming and there were a few of them during 700+ episodes.
The arrival of Spock's parents in Journey to Babel might be on your list, as might the reappearance of the Romulans in The Neutral Zone or how about Tom Paris being demoted in 30 Days?
My choice for Day Eight has to be the loss of Deep Space Nine to the Dominion in the fifth season finale, Call to Arms. War with the Gamma Quadrant power was inevitable and we knew it would end up with something big but the loss of the station itself was never on the cards was it?
Taking away such a key piece of the show was ground-breaking. We could never imagine Kirk or Picard being deprived of the Enterprise for that long (ok...maybe for the odd movie) but the ending was genuinely jaw-dropping and against format since the universe was turning into a less than perfect vision as moulded by Gene Roddenberry.
It was also the longest running twist since the crew didn't get the station back for a subsequent six episodes so there was a lot of change to get used to. Call to Arms is one of my favourite Deep Space Nine's because it took a chance and dared to be different and shock. But I'm sure it wasn't the only one...
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