Event Horizon (1997)
Event Horizon has spent a few years as a point of "so bad it's awesome" reference. The way I remembered it, the first three quarters were stellar science fiction; the conclusion mind-bogglingly ridiculous. I'd enjoyed the beginning so much that I sat there, honestly believing that redemption was just around the corner.
And then came those words: "a dimension of pure evil". That isn't the low point, but it is the point of no return.
The reality doesn't really hold up, though. The first half isn't that great, with too much disgustingly literal foreshadowing. The first time around I must have dismissed out of hand the idea that the warning in Latin was more than a deliberately misleading trope torn from second-rate Exorcist try-hards.
Verdict: the misbegotten spawn of Alien and Hellraiser, more silly than scary.