Films: Altitude (2010)
Location: Eldritch location
Summary: Flying in an airplane is actually a pretty stressful experience you never quite get used to. From the turbulence to the possibility of falling out of the sky, it's a risky venture. Especially if something out of the ordinary happens. Be it slithering reptiles, sharks jumping out from below, or someone accidentally summoning a horrific eldritch monstrosity out of nowhere.
History: A bunch of young jerks have boarded a small private plane for a vacation. Unfortunately, some mistakes and a bit of turbulence lead to them being stranded in a part of the sky where no radio waves travel. Even worse, it turns out that one of the kids is psychic, and his anxiety has manifested in the form of a skyscape from the monster comic he had with him. Said skyscape also contains a massive tentacled beast that has it in for the little people trapped in the plane. Soon, the humans must figure out how to get out of the "Skythulhu"'s clutches and back to land safely.
Notable Kills: Nothing special.
Final Fate: After realizing what willed the Skythulhu into being, the psychic one makes it so that it stops existing, and even time travels in time to save his parents in the process. With that, everything that has happened involving the plane is undone.
Weakness: If that boy decides to calm down and get rid of it, it will be done.
Scariness Factor: 3.5-Sure, the effects aren't the greatest, and the fact that it can be wished away by one isn't all that good either, but just think about that last bit for a second. This gigantic squid-like thing was literally the result of a nerdy guy getting too stressed in the wrong place at the wrong time. And had it not been for the time traveling, lots of people would have been devoured by it and its gaping maw. The fact that we don't quite see all of it is even worse.
Trivia: -Ironically, the author of the comic the boy has is Paul Birkett, this film's director. How clever.
-This wasn't the first time a plane got shanghaied into eldritch territory. Stephen king's "The Langoliers" was a short story written in 1990 that involved a bunch of people accidentally ending up in a dead alternate Earth full of the titular monsters that are almost all toothy mouth, and feast on both man and time itself so that eternity carries on. A 1995 miniseries was based off of this and...well, to call its effects "insanely dated" would be a grave understatement...