These are what we call the 'YMMV items.' Things that some people find in this work. We call them 'your mileage might vary' because not everyone sees these things in the same way. This starts discussions in the trope lists, a thing we don't want. Please use the discussion page if you'd like to discuss any of these items.
YMMV: Event Horizon
Fanon - The movie is considered by many (starting with the community over at /tg/) to be a Spiritual Licensee of Warhammer 40,000, as its storyline coincides perfectly with that setting's history and nature of hyperspace. This isn't enough of a connection on its own to make the instant jump to one particular crossover, but the style and presentation match so well with Warhammer 40k that it's a shock for anyone who watches the movie based solely on this idea to learn that resemblance isn't intentional. Supporting evidence seems to hinge on the film's version of hyperspace bearing a remarkable similarity to what happens to a ship without a Gellar Field.
A Warhammer40k fan who's never seen this movie would easily mistake screen captures showing the horror elements for Chaos at work, right down to the villain's various different looks. The fact that the mundane parts are all dark and gritty helps.
Dark, gritty, covered in corpses, not to mention the Spikes of Doom!
And then there's the Gravity Drive having what looks very suspiciously similar to a Chaos star.
Another segment of fans see Event Horizon as a Hellraiser film. Weir even transforms into a Cenobite for the same reasons that other Cenobites were created: from regret, pain, and loss.
The face that Smith makes when he realizes the Lewis and Clark, which he had just finished fixing is about to explode. Right as he sees the timer on the bomb, his expression is heart-wrenching.
What an Idiot/Too Dumb to Live - Justin walks into the engine room and sees a strange black gateway appear in the centre of the gravity drive. What does he do? Attempt to reach into it. Likewise, when Peters sees a hallucination of her dead son, she wanders off to follow him, knowing full well that the ship is trying to mess with their heads. It gets her killed
Consider both are being mesmerized by whatever it is that is in the ship. Remember, the whole ship is alive. Birds don't want to be mesmerized by snakes, but they are anyway.
The same happens to Dr. Weir ("Open the door.") He's too emotionally weak to withstand the ship.