YMMV / High Tension

• Adaptation Displacement: A "derivative work becomes successful enough to overshadow the original work completely" is especially true here. Hardly anyone knows of Dean Koontz's Intensity, and if they do, they probably know of the book but not the 2-part miniseries. It's why this is available on Netflix and Blockbuster, and Intensity isn't. It's why this is available on Blu-Ray and DVD, and you can only find illegally burned copies of Intensity, or on YouTube before it gets deleted due to copyright violations.
• Ass Pull: The killer being revealed as Marie's Split Personality. One of the most infamous examples outside of M. Night Shyamalan. Critics and filmgoers with both positive and negative things to say about the movie point to this as its biggest flaw, especially regarding the enormous Plot Hole it causes.
• Big-Lipped Alligator Moment: The opening, depicting the killer having sex with a severed head, is retroactively made one after The Reveal.
• Hilarious in Hindsight: Alexandre Aja has said that the scene where the killer searches the bathroom is intended as a Shout-Out to Maniac! (1980). He would later write the screenplay for that film's 2012 remake.
• It Was His Sled: The film's much-maligned Twist Ending is almost as infamous as the movie's violence, with so many critics and filmgoers claiming it ruined an otherwise excellent horror film.
• Spiritual Adaptation: As noted above, to the Dean Koontz novel Intensity. It's also a rare example of a Disowned Spiritual Adaptation, as Koontz considered suing for plagiarism but decided not to because he hated the film so much (specifically, he found it relentlessly grim to the point where he described it as "full of loathing for humanity") that he didn't want it associated with his book, even for the sake of royalties.

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