I don't think I've ever actually been really
scared by Trek. But there's some nice creepy scenes to be had.
One of the best (imho) is an old one: The Beverley morgue scene in
Night Terrors. She is in the morgue, to conduct autopsies, when suddenly she hears something, looks around, and sees all bodies sit right up on the tables -- still covered in shrouds. Bev shudders, walks backwards, bounces into another sitting corpse, realises she must be hallucinating, and says "go away!". Next instant she looks around and everything is as it should be, the corpses lying quietly on the tables again.
Nothing "spectacular". After all those years, still extremely effective in creeping me out
I could put a link to the scene on youtube here, but I believe that is against the forum rules?