Event Horizon doesn't do anything particularly original. The story is an almost textbook haunted-ship yarn, the narrow ship interiors look like some Swedish metalhead set designer reinterpreted Alien, and the images of hellish torment have a strong Clive Barker tone. There's even a big blood flood like The Shining.
It's also kinda dopey. Characters defy common sense outer space search and rescue rules against touching mysterious floating black puddles of goo and chasing after family members they left back on earth. The special effects come from the early days of CGI and they don't hold up well. It commits the cardinal sin of horror cinema: it relies heavily on the amplified volume jump shock.
It also lacks a central protagonist. The movie starts by following Sam Neill's histrionic scientist-on-the-edge, but he quickly falls under the sway of the haunted ship. The focus then switches to Lawrence Fishburne's captain-on-the-edge, who has remained aloof most of the movie and only gets our sympathy after he reveals the Tormenting Incident From His Past.
Despite all this, I still had a lot of fun watching it.
The whole thing is vaguely Lovecraftian. The unfortunate crew of the Event Horizon aren't simply murdered by whatever they encounter during their FTL jump. They go insane, joyfully, maniacally insane. Reality warps around our poor survivors as the ship draws them deeper into its horrible web. We get the sense that the Event Horizon is just the tip of the much grander, much more terrible reality hidden beneath. I like stories that utilize cosmic horror on that scale, and I think sci-fi/horror stories cover that subject well. Most aren't as ambitious as Event Horizon and even when it falls short it should be praised for trying to do something cool.
I also liked the cast. They tend to fall into the classic gruff character types you find in blue collar sci-fi, but they're well acted and appealing, even if the psychological hooks the ship uses against them are completely unsubtle.
It's kind of like a collage of better movies. Still, its worth checking out every few years.