The Next Generation is no different in this regard. Death, fear, and slight horror is present within most episodes, but there are a few standout moments that have stuck with audiences, whether intentional or not.

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This Season 4 episode focuses on the premise that there is a region of space that, for some reason, prevents people from dreaming. The crew of the iconic Enterprise D is tasked with finding a lost Starfleet ship, the USS Brattain, which they find adrift in an unexplored area of space. Riker, Data, Worf, Crusher, and Troi all beam aboard to investigate, and they discover the entire crew has been murdered, apart from a Betazoid who is unresponsive. It turns out that they all were suffering from severe paranoia and delusions from the lack of dreaming. They had all turned on each other, fighting like animals until they had all been killed.

The hallucinations start affecting the enterprise crew, which results in the traumatizing scene. Dr Crusher is collecting brain tissue samples from the dead crew, who are all laid out under plastic sheets in the Brattain’s morgue. She’s alone, except for the dozen or so corpses around her. Suddenly, one behind her sits up, and others around her start moving. It’s a bone-chilling moment, and while it is made clear that this is all happening in her head, it doesn’t make it any less visceral or scary.

Another classic from the 4th season of TNG, this time rather than giving an overall sense of unease or horror throughout the episode, the traumatizing moment is condensed into just one scene. Geordi LaForge, chief of engineering, and two other officers are walking around the ship, after strange things have started happening all over. One of them splits off and walks down a different corridor. What follows is a horrific, blood-curdling scream.

As LaForge and other officer rush to investigate they are met with the half sunken and very dead body of the officer, who has phased through the floor. Blood is dripping from her ear and nose, suggesting that the floor beneath her had suddenly become solid once more as she was passing through, practically cutting her in two. This moment is perhaps more traumatizing as it comes out of nowhere, the officer not even in the typical red uniform signifier of death. It gets more horrific the more thought is given to it, like when considering the logistics of getting her body out. Would they have to cut the floor panel out, or could they just pull her free?

This episode is a great ‘what-if’ moment for the Star Trek series, showing various alternate realities and what would have happened if certain events had never taken place. One such reality shows the enterprise captioned by a deranged Riker, who explains that in his universe the Borg (most likely led by Picard’s Locutus) had managed to destroy the entire Federation, leaving only a handful of ships and crew alive. They are desperately trying to escape the ever-changing Borg, and Riker is a prime example of how the trauma and fear has managed to turn even the hardiest of Starfleet officers mad.

The worst part of the episode, however, is that the moment comes for the alternate reality Enterprise to go back to their reality, something that must happen to restore the correct timeline. At this point, Riker begs them: “We won’t go back, you don’t know what it’s like.” He is terrified, and in a moment of genuine thoughtless fear, he fires upon the prime reality Enterprise to stop them. They fire back and accidentally destroy mad Riker’s Enterprise which, unbeknownst to them, had a damaged warp core.

This episode is a strange one, and traumatizing for an unusual reason. This is the famous episode where Tasha Yar dies at the hands of an alien creator resembling a pit of tar. A lot of fans took issue with this episode. It seriously rattled them, not because she dies, but because her death felt so incredibly pointless and meaningless. She didn’t die for any reason, the alien didn’t gain anything, and she didn’t sacrifice herself to save another. It just killed her, instantly and without reason, just because it could.

There were, of course, behind-the-scenes reasons for this, like her actress wanting to leave the show. But within the confines of the show’s reality, it was brutal. It was a major character death that was so throwaway it left many feeling shaken and confused, the moment sticking with them for years to come.

Apparently, in the 4th season of TNG, the writers had a thing for scaring the socks off their audiences. The trauma of this episode is mainly focused on the way in which they chose to show the shadowy figure during Geordi’s holodeck reconstruction of a strange disappearance, recreated using a mission log. He slowly removes figures, or suspects, from the scenes until there is just one left, a figure that looks to be a physical manifestation of shadow.

The holodeck could not work out who, or what, it was, so created a vague dark outline that triggered a lot of fans as it is akin to that of sleep paralysis and the hallucinations that come with them. When revealed later on what it is, it’s like a cloud of unease is lifted. Often, it is the unknowing that makes it all the more scary.

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