I Am Legend (film)/YMMV


 * Alternate Character Interpretation: Neville's not suffering Sanity Slippage... he just wishes he was. Much of his behavior, such as talking to the mannequins he set up, come off as aping the behavior of someone who's lost it a little, because he thinks life would be easier that way. The "please talk to me" scene comes off more like he's honestly pleading with them to suddenly come to life by virtue of madness, because then he'd have someone to talk to even if he was insane. Sadly, he's not insane... just alone and in pain.
 * High Octane Nightmare Fuel: Neville going into a darkened building, a likely place to find lots of Infected, to search for his dog. He's so obviously terrified you can't help but be frightened with him.
 * Memetic Mutation: GODDAMNIT, FRANK and WOLL SMOTH, which spun into an entirely unrelated meme.
 * Special Effects Failure / Uncanny Valley: The zombie/vamps are pretty obvious CG.
 * Tear Jerker: The aforementioned, and the moment Dr. Neville begs   to say hello to him. Though some found the latter Narmy. Also the "Look Daddy, a butterfly," line right before  . Finally the infected mother begging for her daughter to be taken to safety.
 * The Untwist: At least in the cinematic version.
 * They Wasted a Perfectly Good Plot: The film's alternate ending comes closer to the message of the novel than the ending that made it into the movie and fills the above-mentioned plot hole, in addition to many others. It did poorly with test audiences, though, so Executive Meddling changed it to an ending that has the is completely different and misses the point of the novel entire, twisting the message so that it can still fit the title, but in almost the exact opposite way that the original ending fit it.